Hi Sam, thanks for your comments!

On Fri, Jul 26, 2019 at 11:23:15AM +0200, Sam Ravnborg wrote:

Hi Guido.

A few comments follows.

Sam

On Wed, Jul 24, 2019 at 05:52:25PM +0200, Guido Günther wrote:

...

The Northwest Logic MIPI DSI IP core can be found in NXPs i.MX8 SoCs.

Signed-off-by: Guido Günther agx@sigxcpu.org

.../bindings/display/bridge/imx-nwl-dsi.txt | 89 +++++++++++++++++++

New binding. Any chance we can get this in yaml format? This is the way forward and we have to convert the file anyway.

None of the other bridges use yaml format, but someone has to be the first.

I'm fine with converting this (i also forgot to squash a missing unit name and a typo fix in the bindings, will add this for v2).

...

1 file changed, 89 insertions(+) create mode 100644 Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt

diff --git a/Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt b/Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt new file mode 100644 index 000000000000..288fdb726d5a --- /dev/null +++ b/Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt @@ -0,0 +1,89 @@ +Northwest Logic MIPI-DSI on imx SoCs +=====================================

+NWL MIPI-DSI host controller found on i.MX8 platforms. This is a +dsi bridge for the for the NWL MIPI-DSI host.

To my best understanding a bridge is something that converts from one format to another format. Something that in the drm world are connected to an encoder.

I do not know the HW here - but from this very brif description this sounds more like a display controller and not a bridge?

mxsfb can drive LCD displays directly and - on newer SoCs like the i.MX8 - also feed the nwl dsi host controller. So having that as a bridge is hopefully the right thing to do.

In order for that to work on the hardware i tested on, we'd need:

- at least the first patch from https://patchwork.freedesktop.org/series/62822/ for bridge support - https://patchwork.freedesktop.org/series/64300/ to get the bus flags - https://patchwork.freedesktop.org/series/64292/ to be able to use panel_bridge in this driver

I only had a reference to the first point above in the cover letter. I'll add the other ones for v2 now that these are sent out. I'll also address your comments in other parts of this series.

Cheers and thanks for having look! -- Guido

...

+Required properties: +- compatible: "fsl,<chip>-nwl-dsi"

• The following strings are expected:

• 	"fsl,imx8mq-nwl-dsi"
  

+- reg: the register range of the MIPI-DSI controller +- interrupts: the interrupt number for this module +- clock, clock-names: phandles to the MIPI-DSI clocks

• The following clocks are expected on all platforms:

• "core"    - DSI core clock
  

• "tx_esc"  - TX_ESC clock (used in escape mode)
  

• "rx_esc"  - RX_ESC clock (used in escape mode)
  

• "phy_ref" - PHY_REF clock. Clock is managed by the phy. Only
  

•                        used to read the clock rate.
  

+- assigned-clocks: phandles to clocks that require initial configuration +- assigned-clock-rates: rates of the clocks that require initial configuration

• The following clocks need to have an initial configuration:
• "tx_esc" (20 MHz) and "rx_esc" (80 Mhz).

+- phys: phandle to the phy module representing the DPHY

• 	inside the MIPI-DSI IP block
  

+- phy-names: should be "dphy"

+Optional properties: +- power-domains phandle to the power domain +- src phandle to the system reset controller (required on

• 	i.MX8MQ)
  

Name is not very descriptive. Other bindings seems to use "resets" here?

...

+- mux-sel phandle to the MUX register set (required on i.MX8MQ) +- assigned-clock-parents phandles to parent clocks that needs to be assigned as

• 	parents to clocks defined in assigned-clocks
  

+Example:

• mipi_dsi: mipi_dsi@30a00000 {

• #address-cells = <1>;
  

• #size-cells = <0>;
  

• compatible = "fsl,imx8mq-nwl-dsi";
  

• reg = <0x30A00000 0x300>;
  

• clocks = <&clk IMX8MQ_CLK_DSI_CORE>,
  

• 	 <&clk IMX8MQ_CLK_DSI_AHB>,
  

• 	 <&clk IMX8MQ_CLK_DSI_IPG_DIV>,
  

• 	 <&clk IMX8MQ_CLK_DSI_PHY_REF>;
  

• clock-names = "core", "rx_esc", "tx_esc", "phy_ref";
  

• assigned-clocks = <&clk IMX8MQ_CLK_DSI_AHB>,
  

• 		  <&clk IMX8MQ_CLK_DSI_CORE>,
  

• 		  <&clk IMX8MQ_CLK_DSI_IPG_DIV>;
  

• assigned-clock-parents = <&clk IMX8MQ_SYS1_PLL_80M>,
  

• 			 <&clk IMX8MQ_SYS1_PLL_266M>;
  

• assigned-clock-rates = <80000000>,
  

• 		       <266000000>,
  

• 		       <20000000>;
  

• interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
  

• power-domains = <&pgc_mipi>;
  

• src = <&src>;
  

• mux-sel = <&iomuxc_gpr>;
  

• phys = <&dphy>;
  

• phy-names = "dphy";
  

• status = "okay";
  

I recall status should not be included in examples.

...

• panel@0 {
  

• 	compatible = "...";
  

• 	port {
  

• 	     panel_in: endpoint {
  

• 		       remote-endpoint = <&mipi_dsi_out>;
  

• 	     };
  

• 	};
  

• };
  

• ports {
  

•       #address-cells = <1>;
  

•       #size-cells = <0>;
  

•       port@0 {
  

• 	     reg = <0>;
  

• 	     mipi_dsi_in: endpoint {
  

• 			  remote-endpoint = <&dcss_disp0_mipi_dsi>;
  

• 	     };
  

•       };
  

•       port@1 {
  

• 	     reg = <1>;
  

• 	     mipi_dsi_out: endpoint {
  

• 			   remote-endpoint = <&panel_in>;
  

• 	     };
  

•       };
  

• };
  

• };

-- 2.20.1

---

dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel

Hi Guido,

Thank you for the patch.

On Wed, Jul 24, 2019 at 05:52:25PM +0200, Guido Günther wrote:

The Northwest Logic MIPI DSI IP core can be found in NXPs i.MX8 SoCs.

Signed-off-by: Guido Günther agx@sigxcpu.org

.../bindings/display/bridge/imx-nwl-dsi.txt | 89 +++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt

diff --git a/Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt b/Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt new file mode 100644 index 000000000000..288fdb726d5a --- /dev/null +++ b/Documentation/devicetree/bindings/display/bridge/imx-nwl-dsi.txt @@ -0,0 +1,89 @@ +Northwest Logic MIPI-DSI on imx SoCs +=====================================

There's one too many =.

+NWL MIPI-DSI host controller found on i.MX8 platforms. This is a +dsi bridge for the for the NWL MIPI-DSI host.

s/dsi/DSI/ s/for the for the /for the /

+Required properties: +- compatible: "fsl,<chip>-nwl-dsi"

• The following strings are expected:

• 	"fsl,imx8mq-nwl-dsi"
  

+- reg: the register range of the MIPI-DSI controller +- interrupts: the interrupt number for this module

It's not just a number but a specifier (with flags).

+- clock, clock-names: phandles to the MIPI-DSI clocks

That should be phandles and names.

• The following clocks are expected on all platforms:

Expected or required ?

s/ on all platforms// as you only support a single platform.

• "core"    - DSI core clock
  

• "tx_esc"  - TX_ESC clock (used in escape mode)
  

• "rx_esc"  - RX_ESC clock (used in escape mode)
  

• "phy_ref" - PHY_REF clock. Clock is managed by the phy. Only
  

•                        used to read the clock rate.
  

+- assigned-clocks: phandles to clocks that require initial configuration +- assigned-clock-rates: rates of the clocks that require initial configuration

• The following clocks need to have an initial configuration:
• "tx_esc" (20 MHz) and "rx_esc" (80 Mhz).

I think those two properties are out of scope for these bindings.

+- phys: phandle to the phy module representing the DPHY

• 	inside the MIPI-DSI IP block
  

+- phy-names: should be "dphy"

+Optional properties: +- power-domains phandle to the power domain +- src phandle to the system reset controller (required on

• 	i.MX8MQ)
  

Should this use the standard resets property ?

+- mux-sel phandle to the MUX register set (required on i.MX8MQ) +- assigned-clock-parents phandles to parent clocks that needs to be assigned as

• 	parents to clocks defined in assigned-clocks
  

This property is also out of scope.

+Example:

• mipi_dsi: mipi_dsi@30a00000 {

• #address-cells = <1>;
  

• #size-cells = <0>;
  

• compatible = "fsl,imx8mq-nwl-dsi";
  

• reg = <0x30A00000 0x300>;
  

• clocks = <&clk IMX8MQ_CLK_DSI_CORE>,
  

• 	 <&clk IMX8MQ_CLK_DSI_AHB>,
  

• 	 <&clk IMX8MQ_CLK_DSI_IPG_DIV>,
  

• 	 <&clk IMX8MQ_CLK_DSI_PHY_REF>;
  

• clock-names = "core", "rx_esc", "tx_esc", "phy_ref";
  

• assigned-clocks = <&clk IMX8MQ_CLK_DSI_AHB>,
  

• 		  <&clk IMX8MQ_CLK_DSI_CORE>,
  

• 		  <&clk IMX8MQ_CLK_DSI_IPG_DIV>;
  

• assigned-clock-parents = <&clk IMX8MQ_SYS1_PLL_80M>,
  

• 			 <&clk IMX8MQ_SYS1_PLL_266M>;
  

• assigned-clock-rates = <80000000>,
  

• 		       <266000000>,
  

• 		       <20000000>;
  

• interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
  

• power-domains = <&pgc_mipi>;
  

• src = <&src>;
  

• mux-sel = <&iomuxc_gpr>;
  

• phys = <&dphy>;
  

• phy-names = "dphy";
  

• status = "okay";
  

• panel@0 {
  

• 	compatible = "...";
  

• 	port {
  

• 	     panel_in: endpoint {
  

• 		       remote-endpoint = <&mipi_dsi_out>;
  

• 	     };
  

• 	};
  

• };
  

• ports {
  

•       #address-cells = <1>;
  

•       #size-cells = <0>;
  

•       port@0 {
  

• 	     reg = <0>;
  

• 	     mipi_dsi_in: endpoint {
  

• 			  remote-endpoint = <&dcss_disp0_mipi_dsi>;
  

• 	     };
  

•       };
  

•       port@1 {
  

• 	     reg = <1>;
  

• 	     mipi_dsi_out: endpoint {
  

• 			   remote-endpoint = <&panel_in>;
  

• 	     };
  

•       };
  

• };
  

The ports should be documented too. There are multiple example bindings available.

• };

Hi Guido,

Thanks for your work on this driver!

On Wed, Jul 24, 2019 at 12:52 PM Guido Günther agx@sigxcpu.org wrote:

--- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/Kconfig @@ -0,0 +1,15 @@ +config DRM_IMX_NWL_DSI

•   tristate "Support for Northwest Logic MIPI DSI Host controller"
  

•   depends on DRM && (ARCH_MXC || ARCH_MULTIPLATFORM || COMPILE_TEST)
  

This IP could potentially be found on other SoCs, so no need to make it depend on ARCH_MXC.

+#include <drm/drm_atomic_helper.h> +#include <drm/drm_of.h> +#include <drm/drm_panel.h> +#include <drm/drm_print.h> +#include <drm/drm_probe_helper.h> +#include <linux/clk-provider.h> +#include <linux/clk.h> +#include <linux/component.h> +#include <linux/gpio/consumer.h>

I did not find gpio AP used in this driver.

+static void imx_nwl_dsi_set_clocks(struct imx_nwl_dsi *dsi, bool enable)

Better make it to return 'int' instead...

+{

•   struct device *dev = dsi->dev;
  

•   const char *id;
  

•   struct clk *clk;
  

•   unsigned long new_rate, cur_rate;
  

•   bool enabled;
  

•   size_t i;
  

•   int ret;
  

•   DRM_DEV_DEBUG_DRIVER(dev, "%sabling platform clocks",
  

Please remove the letter 's' from 'sabling'.

•                        enable ? "en" : "dis");
  

•                   ret = clk_prepare_enable(clk);
  

•                   if (ret < 0) {
  

•                           DRM_DEV_ERROR(dev, "Failed to enable clock %s",
  

•                                         id);
  

and propagate the error in case of clk_prepare_enable() failure.

•                   }
  

•                   dsi->clk_config[i].enabled = true;
  

•                   cur_rate = clk_get_rate(clk);
  

•                   DRM_DEV_DEBUG_DRIVER(
  

•                           dev, "Enabled %s clk (rate: req=%lu act=%lu)\n",
  

•                           id, new_rate, cur_rate);
  

•           } else if (enabled) {
  

•                   clk_disable_unprepare(clk);
  

•                   dsi->clk_config[i].enabled = false;
  

•                   DRM_DEV_DEBUG_DRIVER(dev, "Disabled %s clk\n", id);
  

•           }
  

•   }
  

+}

+static void imx_nwl_dsi_enable(struct imx_nwl_dsi *dsi)

Same here. Please return 'int' instead.

+{

•   struct device *dev = dsi->dev;
  

•   int ret;
  

•   imx_nwl_dsi_set_clocks(dsi, true);
  

•   ret = dsi->pdata->poweron(dsi);
  

•   if (ret < 0)
  

•           DRM_DEV_ERROR(dev, "Failed to power on DSI (%d)\n", ret);
  

If the power domain failed to turn on, it is better to propagate the error.

•   phy_ref_rate = clk_get_rate(dsi->phy_ref_clk);
  

•   DRM_DEV_DEBUG_DRIVER(dev, "PHY at ref rate: %lu\n", phy_ref_rate);
  

•   if (ret < 0) {
  

This check looks wrong. At this point ret is always 0.

•           DRM_DEV_ERROR(dsi->dev,
  

•                         "Cannot setup PHY for mode: %ux%u @%d Hz\n",
  

•                         adjusted_mode->hdisplay, adjusted_mode->vdisplay,
  

•                         adjusted_mode->clock);
  

•           DRM_DEV_ERROR(dsi->dev, "PHY ref clk: %lu, bit clk: %lu\n",
  

•                         phy_ref_rate, new_cfg.mipi_dphy.hs_clk_rate);
  

•   } else {
  

•           /* Save the new desired phy config */
  

•           memcpy(&dsi->phy_cfg, &new_cfg, sizeof(new_cfg));
  

•   }
  

•   /* LCDIF + NWL needs active high sync */
  

Would this still work if DCSS is used instead?

•   adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
  

•   adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
  

•   drm_display_mode_to_videomode(adjusted_mode, &dsi->vm);
  

•   drm_mode_debug_printmodeline(adjusted_mode);
  

•   return ret == 0;
  

At this point ret is always 0.

+static void imx_nwl_dsi_bridge_pre_enable(struct drm_bridge *bridge) +{

•   struct imx_nwl_dsi *dsi = bridge_to_dsi(bridge);
  

•   if (dsi->dpms_mode == DRM_MODE_DPMS_ON)
  

•           return;
  

•   imx_nwl_select_input_source(dsi);
  

This function is i.MX8M specific, so better protect it to run only for the i.MX8M variant.

•   pm_runtime_get_sync(dsi->dev);
  

•   imx_nwl_dsi_enable(dsi);
  

•   nwl_dsi_enable(dsi);
  

Please check the error and propagate in the case of failure.

•   dsi->dpms_mode = DRM_MODE_DPMS_ON;
  

+}

•   dsi->csr = syscon_regmap_lookup_by_phandle(np, "csr");
  

•   if (IS_ERR(dsi->csr) && dsi->pdata->ext_regs & IMX_REG_CSR) {
  

•           ret = PTR_ERR(dsi->csr);
  

•           DRM_DEV_ERROR(dsi->dev, "Failed to get CSR regmap: %d\n",
  

In this function (and globally in the driver) there is a mix of DRM_DEV_ERROR() and dev_err().

Can we just pick one of the two and use it consistently?

Not sure what is the norm in drm code, but IMHO dev_err() looks prettier :-)

•   res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  

•   base = devm_ioremap_resource(dsi->dev, res);
  

Could use devm_platform_ioremap_resource(), which makes it simpler.

+err_cleanup:

•   devm_free_irq(dev, dsi->irq, dsi);
  

No need to call devm_free_irq() here. The devm functions do not need to be freed on probe.

diff --git a/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c b/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c new file mode 100644 index 000000000000..0e1463af162f --- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c @@ -0,0 +1,745 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • NWL DSI host driver
• • Copyright (C) 2017 NXP
• • Copyright (C) 2019 Purism SPC
• */

+#include <asm/unaligned.h>

Is this asm header required?

+/*

• • DSI Video mode
• */

Single line comment would suffice.

+#define VIDEO_MODE_BURST_MODE_WITH_SYNC_PULSES 0 +#define VIDEO_MODE_NON_BURST_MODE_WITH_SYNC_EVENTS BIT(0) +#define VIDEO_MODE_BURST_MODE BIT(1)

+/*

• • DPI color coding
• */

Ditto.

+#define DPI_16_BIT_565_PACKED 0 +#define DPI_16_BIT_565_ALIGNED 1 +#define DPI_16_BIT_565_SHIFTED 2 +#define DPI_18_BIT_PACKED 3 +#define DPI_18_BIT_ALIGNED 4 +#define DPI_24_BIT 5

+/*

• • DPI Pixel format
• */

Ditto.

+#define PIXEL_FORMAT_16 0 +#define PIXEL_FORMAT_18 BIT(0) +#define PIXEL_FORMAT_18L BIT(1) +#define PIXEL_FORMAT_24 (BIT(0) | BIT(1))

+enum transfer_direction { DSI_PACKET_SEND, DSI_PACKET_RECEIVE };

+struct mipi_dsi_transfer {

•   const struct mipi_dsi_msg *msg;
  

•   struct mipi_dsi_packet packet;
  

•   struct completion completed;
  

•   int status; /* status of transmission */
  

•   enum transfer_direction direction;
  

•   bool need_bta;
  

•   u8 cmd;
  

•   u16 rx_word_count;
  

•   size_t tx_len; /* bytes sent */
  

•   size_t rx_len; /* bytes received */
  

+};

The comments here are kind of obvious, so I would just remove them.

+static inline int nwl_dsi_write(struct imx_nwl_dsi *dsi, unsigned int reg,

inline can be dropped.

•                           u32 val)
  

+{

•   int ret;
  

•   ret = regmap_write(dsi->regmap, reg, val);
  

•   if (ret < 0)
  

•           DRM_DEV_ERROR(dsi->dev,
  

•                         "Failed to write NWL DSI reg 0x%x: %d\n", reg,
  

•                         ret);
  

•   return ret;
  

+}

+static inline u32 nwl_dsi_read(struct imx_nwl_dsi *dsi, u32 reg)

Same here.

+{

•   unsigned int val;
  

•   int ret;
  

•   ret = regmap_read(dsi->regmap, reg, &val);
  

•   if (ret < 0)
  

•           DRM_DEV_ERROR(dsi->dev, "Failed to read NWL DSI reg 0x%x: %d\n",
  

•                         reg, ret);
  

•   return val;
  

+}

It seems that we could simply use regmap_read/write() directly instead of these functions.

+int nwl_dsi_get_dphy_params(struct imx_nwl_dsi *dsi,

•                       const struct drm_display_mode *mode,
  

•                       union phy_configure_opts *phy_opts)
  

+{

•   unsigned long rate;
  

•   if (dsi->lanes < 1 || dsi->lanes > 4)
  

•           return -EINVAL;
  

•   /*
  

•    * So far the DPHY spec minimal timings work for both mixel
  

•    * dphy and nwl dsi host
  

•    */
  

•   phy_mipi_dphy_get_default_config(
  

•           mode->crtc_clock * 1000,
  

•           mipi_dsi_pixel_format_to_bpp(dsi->format), dsi->lanes,
  

•           &phy_opts->mipi_dphy);
  

•   rate = clk_get_rate(dsi->tx_esc_clk);
  

•   DRM_DEV_DEBUG_DRIVER(dsi->dev, "LP clk is @%lu Hz\n", rate);
  

•   phy_opts->mipi_dphy.lp_clk_rate = rate;
  

•   return 0;
  

+} +EXPORT_SYMBOL_GPL(nwl_dsi_get_dphy_params);

Does it really need to be exported? Why can't it be placed inside nwl-drv.c and be made static?

+/**

/* is enough

• • ui2bc - UI time periods to byte clock cycles
• */

+static u32 ui2bc(struct imx_nwl_dsi *dsi, unsigned long long ui) +{

•   int bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
  

•   return DIV_ROUND_UP(ui * dsi->lanes, dsi->vm.pixelclock * bpp);
  

+}

+#define USEC_PER_SEC 1000000L

This definition already exists in include/linux/time64.h. No need to redefine it.

+static int nwl_dsi_enable_tx_clock(struct imx_nwl_dsi *dsi) +{

•   struct device *dev = dsi->dev;
  

•   int ret;
  

•   ret = clk_prepare_enable(dsi->tx_esc_clk);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to enable tx_esc clk: %d\n", ret);
  

•           return ret;
  

•   }
  

•   DRM_DEV_DEBUG_DRIVER(dev, "Enabled tx_esc clk @%lu Hz\n",
  

•                        clk_get_rate(dsi->tx_esc_clk));
  

•   return 0;
  

+}

Do we really need this function? It looks like it would be simpler just to call clk_prepare_enable() directly.

+static int nwl_dsi_enable_rx_clock(struct imx_nwl_dsi *dsi) +{

•   struct device *dev = dsi->dev;
  

•   int ret;
  

•   ret = clk_prepare_enable(dsi->rx_esc_clk);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to enable rx_esc clk: %d\n", ret);
  

•           return ret;
  

•   }
  

•   DRM_DEV_DEBUG_DRIVER(dev, "Enabled rx_esc clk @%lu Hz\n",
  

•                        clk_get_rate(dsi->rx_esc_clk));
  

•   return 0;
  

+}

Same here.

+static ssize_t nwl_dsi_host_transfer(struct mipi_dsi_host *dsi_host,

•                                const struct mipi_dsi_msg *msg)
  

+{

•   struct imx_nwl_dsi *dsi =
  

•           container_of(dsi_host, struct imx_nwl_dsi, dsi_host);
  

•   struct mipi_dsi_transfer xfer;
  

•   ssize_t ret = 0;
  

•   /* Create packet to be sent */
  

•   dsi->xfer = &xfer;
  

•   ret = mipi_dsi_create_packet(&xfer.packet, msg);
  

•   if (ret < 0) {
  

•           dsi->xfer = NULL;
  

•           return ret;
  

•   }
  

•   if ((msg->type & MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM ||
  

•        msg->type & MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM ||
  

•        msg->type & MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM ||
  

•        msg->type & MIPI_DSI_DCS_READ) &&
  

•       msg->rx_len > 0 && msg->rx_buf != NULL)
  

•           xfer.direction = DSI_PACKET_RECEIVE;
  

•   else
  

•           xfer.direction = DSI_PACKET_SEND;
  

•   xfer.need_bta = (xfer.direction == DSI_PACKET_RECEIVE);
  

•   xfer.need_bta |= (msg->flags & MIPI_DSI_MSG_REQ_ACK) ? 1 : 0;
  

•   xfer.msg = msg;
  

•   xfer.status = -ETIMEDOUT;
  

•   xfer.rx_word_count = 0;
  

•   xfer.rx_len = 0;
  

•   xfer.cmd = 0x00;
  

•   if (msg->tx_len > 0)
  

•           xfer.cmd = ((u8 *)(msg->tx_buf))[0];
  

•   init_completion(&xfer.completed);
  

•   nwl_dsi_enable_rx_clock(dsi);
  

This may fail, so better check the error.

ret = clk_prepare_enable() if (ret < 0) return ret;

+irqreturn_t nwl_dsi_irq_handler(int irq, void *data) +{

•   u32 irq_status;
  

•   struct imx_nwl_dsi *dsi = data;
  

•   irq_status = nwl_dsi_read(dsi, IRQ_STATUS);
  

•   if (irq_status & TX_PKT_DONE || irq_status & RX_PKT_HDR_RCVD ||
  

•       irq_status & RX_PKT_PAYLOAD_DATA_RCVD)
  

•           nwl_dsi_finish_transmission(dsi, irq_status);
  

•   return IRQ_HANDLED;
  

+} +EXPORT_SYMBOL_GPL(nwl_dsi_irq_handler);

What about placing this function inside nwl-drv.c and make it static?

+int nwl_dsi_enable(struct imx_nwl_dsi *dsi) +{

•   struct device *dev = dsi->dev;
  

•   union phy_configure_opts *phy_cfg = &dsi->phy_cfg;
  

•   int ret;
  

•   if (!dsi->lanes) {
  

•           DRM_DEV_ERROR(dev, "Need DSI lanes: %d\n", dsi->lanes);
  

•           return -EINVAL;
  

•   }
  

•   ret = phy_init(dsi->phy);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to init DSI phy: %d\n", ret);
  

•           return ret;
  

•   }
  

•   ret = phy_configure(dsi->phy, phy_cfg);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to configure DSI phy: %d\n", ret);
  

•           return ret;
  

•   }
  

•   ret = nwl_dsi_enable_tx_clock(dsi);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to enable tx clock: %d\n", ret);
  

•           return ret;
  

•   }
  

•   ret = nwl_dsi_config_host(dsi);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to set up DSI: %d", ret);
  

•           return ret;
  

•   }
  

•   ret = nwl_dsi_config_dpi(dsi);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to set up DPI: %d", ret);
  

•           return ret;
  

•   }
  

•   ret = phy_power_on(dsi->phy);
  

•   if (ret < 0) {
  

•           DRM_DEV_ERROR(dev, "Failed to power on DPHY (%d)\n", ret);
  

•           return ret;
  

•   }
  

•   nwl_dsi_init_interrupts(dsi);
  

•   return 0;
  

+} +EXPORT_SYMBOL_GPL(nwl_dsi_enable);

Same here.

+int nwl_dsi_disable(struct imx_nwl_dsi *dsi) +{

•   struct device *dev = dsi->dev;
  

•   DRM_DEV_DEBUG_DRIVER(dev, "Disabling clocks and phy\n");
  

•   phy_power_off(dsi->phy);
  

•   phy_exit(dsi->phy);
  

•   /* Disabling the clock before the phy breaks enabling dsi again */
  

•   clk_disable_unprepare(dsi->tx_esc_clk);
  

•   return 0;
  

+} +EXPORT_SYMBOL_GPL(nwl_dsi_disable);

Same here.

Hi, On Sat, Jul 27, 2019 at 05:04:44AM +0300, Laurent Pinchart wrote:

Hello,

On Fri, Jul 26, 2019 at 05:01:52PM -0300, Fabio Estevam wrote:

...

Hi Guido,

Thanks for your work on this driver!

On Wed, Jul 24, 2019 at 12:52 PM Guido Günther agx@sigxcpu.org wrote:

...

--- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/Kconfig @@ -0,0 +1,15 @@ +config DRM_IMX_NWL_DSI

•   tristate "Support for Northwest Logic MIPI DSI Host controller"
  

•   depends on DRM && (ARCH_MXC || ARCH_MULTIPLATFORM || COMPILE_TEST)
  

This IP could potentially be found on other SoCs, so no need to make it depend on ARCH_MXC.

I'd go even further and not use the prefix imx in the driver name or anywhere in the code.

My idea was to do that when another possible user comes up to see what can be shared but I can do that for v2. Cheers, -- Guido

[snip]

-- Regards,

Laurent Pinchart

Hello Guido,

Thank you for the patch.

On Wed, Jul 24, 2019 at 05:52:26PM +0200, Guido Günther wrote:

This adds initial support for the NWL MIPI DSI Host controller found on i.MX8 SoCs.

It adds support for the i.MX8MQ but the same IP can be found on e.g. the i.MX8QXP.

It has been tested on the Librem 5 devkit using mxsfb.

Signed-off-by: Guido Günther agx@sigxcpu.org Co-developed-by: Robert Chiras robert.chiras@nxp.com

---

drivers/gpu/drm/bridge/Kconfig | 2 + drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/imx-nwl/Kconfig | 15 + drivers/gpu/drm/bridge/imx-nwl/Makefile | 2 + drivers/gpu/drm/bridge/imx-nwl/nwl-drv.c | 529 ++++++++++++++++ drivers/gpu/drm/bridge/imx-nwl/nwl-drv.h | 72 +++ drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c | 745 +++++++++++++++++++++++ drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.h | 111 ++++ 8 files changed, 1477 insertions(+) create mode 100644 drivers/gpu/drm/bridge/imx-nwl/Kconfig create mode 100644 drivers/gpu/drm/bridge/imx-nwl/Makefile create mode 100644 drivers/gpu/drm/bridge/imx-nwl/nwl-drv.c create mode 100644 drivers/gpu/drm/bridge/imx-nwl/nwl-drv.h create mode 100644 drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c create mode 100644 drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.h

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index a6eec908c43e..38c3145a7e57 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -152,6 +152,8 @@ source "drivers/gpu/drm/bridge/analogix/Kconfig"

source "drivers/gpu/drm/bridge/adv7511/Kconfig"

+source "drivers/gpu/drm/bridge/imx-nwl/Kconfig"

As this doesn't seem to be an i.MX-specific IP, I wouldn't use the name imx in file names or in the code, at least in the parts that are not NXP-specific.

source "drivers/gpu/drm/bridge/synopsys/Kconfig"

endmenu diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index 4934fcf5a6f8..904a9eb3a20a 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -16,4 +16,5 @@ obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/ obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/ obj-$(CONFIG_DRM_TI_SN65DSI86) += ti-sn65dsi86.o obj-$(CONFIG_DRM_TI_TFP410) += ti-tfp410.o +obj-y += imx-nwl/ obj-y += synopsys/ diff --git a/drivers/gpu/drm/bridge/imx-nwl/Kconfig b/drivers/gpu/drm/bridge/imx-nwl/Kconfig new file mode 100644 index 000000000000..822dba1b380a --- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/Kconfig @@ -0,0 +1,15 @@ +config DRM_IMX_NWL_DSI

• tristate "Support for Northwest Logic MIPI DSI Host controller"
• depends on DRM && (ARCH_MXC || ARCH_MULTIPLATFORM || COMPILE_TEST)
• depends on COMMON_CLK
• depends on OF && HAS_IOMEM
• select DRM_KMS_HELPER
• select DRM_MIPI_DSI
• select DRM_PANEL_BRIDGE
• select GENERIC_PHY_MIPI_DPHY
• select MFD_SYSCON
• select REGMAP_MMIO
• help

•  This enables the Northwest Logic MIPI DSI Host controller as
  

•  found on NXP's i.MX8 Processors.
  

diff --git a/drivers/gpu/drm/bridge/imx-nwl/Makefile b/drivers/gpu/drm/bridge/imx-nwl/Makefile new file mode 100644 index 000000000000..9fa63483da5b --- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/Makefile @@ -0,0 +1,2 @@ +imx-nwl-objs := nwl-drv.o nwl-dsi.o +obj-$(CONFIG_DRM_IMX_NWL_DSI) += imx-nwl.o diff --git a/drivers/gpu/drm/bridge/imx-nwl/nwl-drv.c b/drivers/gpu/drm/bridge/imx-nwl/nwl-drv.c new file mode 100644 index 000000000000..451f8f067c6f --- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/nwl-drv.c @@ -0,0 +1,529 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • i.MX8 NWL MIPI DSI host driver
• • Copyright (C) 2017 NXP
• • Copyright (C) 2019 Purism SPC
• */

+#include <drm/drm_atomic_helper.h> +#include <drm/drm_of.h> +#include <drm/drm_panel.h> +#include <drm/drm_print.h> +#include <drm/drm_probe_helper.h> +#include <linux/clk-provider.h>

This doesn't seem to be needed.

+#include <linux/clk.h> +#include <linux/component.h>

Same here.

+#include <linux/gpio/consumer.h> +#include <linux/irq.h> +#include <linux/mfd/syscon.h> +#include <linux/mfd/syscon/imx8mq-iomuxc-gpr.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/phy/phy.h> +#include <linux/regmap.h> +#include <linux/sys_soc.h> +#include <video/videomode.h>

+#include "nwl-drv.h" +#include "nwl-dsi.h"

+#define DRV_NAME "imx-nwl-dsi"

+/* 8MQ SRC specific registers */ +#define SRC_MIPIPHY_RCR 0x28 +#define RESET_BYTE_N BIT(1) +#define RESET_N BIT(2) +#define DPI_RESET_N BIT(3) +#define ESC_RESET_N BIT(4) +#define PCLK_RESET_N BIT(5)

+/* Possible clocks */ +#define CLK_PIXEL "pixel" +#define CLK_CORE "core" +#define CLK_BYPASS "bypass"

+enum imx_ext_regs {

• IMX_REG_CSR = BIT(1),
• IMX_REG_SRC = BIT(2),
• IMX_REG_GPR = BIT(3),

+};

+static const struct regmap_config nwl_dsi_regmap_config = {

• .reg_bits = 16,
• .val_bits = 32,
• .reg_stride = 4,
• .max_register = IRQ_MASK2,
• .name = DRV_NAME,

+};

+struct imx_nwl_platform_data {

• int (*poweron)(struct imx_nwl_dsi *dsi);
• int (*poweroff)(struct imx_nwl_dsi *dsi);
• u32 ext_regs; /* required external registers */
• struct imx_nwl_clk_config clk_config[NWL_MAX_PLATFORM_CLOCKS];

+};

+static inline struct imx_nwl_dsi *bridge_to_dsi(struct drm_bridge *bridge) +{

• return container_of(bridge, struct imx_nwl_dsi, bridge);

+}

+static void imx_nwl_dsi_set_clocks(struct imx_nwl_dsi *dsi, bool enable) +{

• struct device *dev = dsi->dev;
• const char *id;
• struct clk *clk;
• unsigned long new_rate, cur_rate;
• bool enabled;
• size_t i;
• int ret;
• DRM_DEV_DEBUG_DRIVER(dev, "%sabling platform clocks",

• 	     enable ? "en" : "dis");
  

• for (i = 0; i < ARRAY_SIZE(dsi->pdata->clk_config); i++) {

• if (!dsi->clk_config[i].present)
  

• 	continue;
  

• id = dsi->clk_config[i].id;
  

• clk = dsi->clk_config[i].clk;
  

• new_rate = dsi->clk_config[i].rate;
  

• cur_rate = clk_get_rate(clk);
  

• enabled = dsi->clk_config[i].enabled;
  

• /* BYPASS clk must have the same rate as PHY_REF clk */
  

• if (!strcmp(id, CLK_BYPASS))
  

• 	new_rate = clk_get_rate(dsi->phy_ref_clk);
  

• if (enable) {
  

• 	if (enabled && new_rate != cur_rate)
  

• 		clk_disable_unprepare(clk);
  

• 	else if (enabled && new_rate == cur_rate)
  

• 		continue;
  

• 	if (new_rate > 0)
  

• 		clk_set_rate(clk, new_rate);
  

• 	ret = clk_prepare_enable(clk);
  

• 	if (ret < 0) {
  

• 		DRM_DEV_ERROR(dev, "Failed to enable clock %s",
  

• 			      id);
  

• 	}
  

• 	dsi->clk_config[i].enabled = true;
  

• 	cur_rate = clk_get_rate(clk);
  

• 	DRM_DEV_DEBUG_DRIVER(
  

• 		dev, "Enabled %s clk (rate: req=%lu act=%lu)\n",
  

• 		id, new_rate, cur_rate);
  

• } else if (enabled) {
  

• 	clk_disable_unprepare(clk);
  

• 	dsi->clk_config[i].enabled = false;
  

• 	DRM_DEV_DEBUG_DRIVER(dev, "Disabled %s clk\n", id);
  

• }
  

• }

+}

+static void imx_nwl_dsi_enable(struct imx_nwl_dsi *dsi) +{

• struct device *dev = dsi->dev;
• int ret;
• imx_nwl_dsi_set_clocks(dsi, true);
• ret = dsi->pdata->poweron(dsi);
• if (ret < 0)

• DRM_DEV_ERROR(dev, "Failed to power on DSI (%d)\n", ret);
  

+}

+static void imx_nwl_dsi_disable(struct imx_nwl_dsi *dsi) +{

• struct device *dev = dsi->dev;
• if (dsi->dpms_mode != DRM_MODE_DPMS_ON)

• return;
  

The DRM core should guarantee that the bridge won't be disabled twice, so I don't think you need this check. Similarly I think the enabled flag in the imx_nwl_clk_config structure can be removed.

• DRM_DEV_DEBUG_DRIVER(dev, "Disabling encoder");

Is this really needed ?

• dsi->pdata->poweroff(dsi);
• imx_nwl_dsi_set_clocks(dsi, false);

+}

+static void imx_nwl_select_input_source(struct imx_nwl_dsi *dsi) +{

• struct device_node *remote;
• u32 mux_val = IMX8MQ_GPR13_MIPI_MUX_SEL;
• remote = of_graph_get_remote_node(dsi->dev->of_node, 0, 0);
• if (strcmp(remote->name, "lcdif") == 0)

• mux_val = 0;
  

Can't you check the remote node at probe time instead of every time the bridge gets enabled, and program the IO mux accordingly there ?

This code is i.MX-specific, so it should be isolated in an operation in struct imx_nwl_platform_data.

• DRM_DEV_INFO(dsi->dev, "Using %s as input source\n",

•      (mux_val) ? "DCSS" : "LCDIF");
  

• regmap_update_bits(dsi->mux_sel, IOMUXC_GPR13,

• 	   IMX8MQ_GPR13_MIPI_MUX_SEL, mux_val);
  

• of_node_put(remote);

+}

+static void imx_nwl_dsi_bridge_disable(struct drm_bridge *bridge) +{

• struct imx_nwl_dsi *dsi = bridge_to_dsi(bridge);
• if (dsi->dpms_mode != DRM_MODE_DPMS_ON)

• return;
  

• nwl_dsi_disable(dsi);
• imx_nwl_dsi_disable(dsi);
• pm_runtime_put_sync(dsi->dev);

Do you need a put_sync, wouldn't a put do ?

• dsi->dpms_mode = DRM_MODE_DPMS_OFF;

+}

+static bool +imx_nwl_dsi_bridge_mode_fixup(struct drm_bridge *bridge,

• 	      const struct drm_display_mode *mode,
  

• 	      struct drm_display_mode *adjusted_mode)
  

+{

• struct imx_nwl_dsi *dsi = bridge_to_dsi(bridge);
• struct device *dev = dsi->dev;
• union phy_configure_opts new_cfg;
• unsigned long phy_ref_rate;
• int ret;
• ret = nwl_dsi_get_dphy_params(dsi, adjusted_mode, &new_cfg);
• if (ret < 0)

• return ret;
  

• /*

• * If hs clock is unchanged, we're all good - all parameters are
  

• * derived from it atm.
  

• */
  

• if (new_cfg.mipi_dphy.hs_clk_rate == dsi->phy_cfg.mipi_dphy.hs_clk_rate)

• return true;
  

• phy_ref_rate = clk_get_rate(dsi->phy_ref_clk);
• DRM_DEV_DEBUG_DRIVER(dev, "PHY at ref rate: %lu\n", phy_ref_rate);
• if (ret < 0) {

This can't happen. Or are you missing a function call before the check ?

• DRM_DEV_ERROR(dsi->dev,
  

• 	      "Cannot setup PHY for mode: %ux%u @%d Hz\n",
  

• 	      adjusted_mode->hdisplay, adjusted_mode->vdisplay,
  

• 	      adjusted_mode->clock);
  

• DRM_DEV_ERROR(dsi->dev, "PHY ref clk: %lu, bit clk: %lu\n",
  

• 	      phy_ref_rate, new_cfg.mipi_dphy.hs_clk_rate);
  

• } else {

• /* Save the new desired phy config */
  

• memcpy(&dsi->phy_cfg, &new_cfg, sizeof(new_cfg));
  

The mode_fixup operation shall not change the device state, it can be called multiple times when trying modes.

• }
• /* LCDIF + NWL needs active high sync */
• adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
• adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
• drm_display_mode_to_videomode(adjusted_mode, &dsi->vm);
• drm_mode_debug_printmodeline(adjusted_mode);
• return ret == 0;

return 0;

+}

+static enum drm_mode_status +imx_nwl_dsi_bridge_mode_valid(struct drm_bridge *bridge,

• 	      const struct drm_display_mode *mode)
  

+{

• struct imx_nwl_dsi *dsi = bridge_to_dsi(bridge);
• int bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
• if (bpp < 0) {

• DRM_DEV_ERROR(dsi->dev, "Invalid pixel format: %d\n",
  

• 	      dsi->format);
  

• return MODE_BAD;
  

• }

The format isn't part of the mode, so this doesn't belong here. You should here instead check that the mode clock and other timing data (especially the visible resolution) are within the range supported by the device.

• return MODE_OK;

+}

+static void imx_nwl_dsi_bridge_pre_enable(struct drm_bridge *bridge) +{

• struct imx_nwl_dsi *dsi = bridge_to_dsi(bridge);
• if (dsi->dpms_mode == DRM_MODE_DPMS_ON)

• return;
  

• imx_nwl_select_input_source(dsi);
• pm_runtime_get_sync(dsi->dev);
• imx_nwl_dsi_enable(dsi);
• nwl_dsi_enable(dsi);
• dsi->dpms_mode = DRM_MODE_DPMS_ON;

+}

+static int imx_nwl_dsi_bridge_attach(struct drm_bridge *bridge) +{

• struct imx_nwl_dsi *dsi = bridge->driver_private;
• struct drm_encoder *encoder = bridge->encoder;
• if (!encoder) {

• DRM_DEV_ERROR(dsi->dev, "Parent encoder object not found\n");
  

• return -ENODEV;
  

• }

Can't this happen ?

• /* Set the encoder type as caller does not know it */
• bridge->encoder->encoder_type = DRM_MODE_ENCODER_DSI;

The encoder type is quite meaningless and userspace should not depend on it, so I wouldn't set it here, especially that the encoder may not expect the bridge to override its type.

• /* Attach the panel-bridge to the dsi bridge */
• return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, bridge);

+}

+static void imx_nwl_dsi_bridge_detach(struct drm_bridge *bridge) +{

• struct imx_nwl_dsi *dsi = bridge->driver_private;
• drm_of_panel_bridge_remove(dsi->dev->of_node, 1, 0);

This is already done in nwl_dsi_host_detach().

+}

+/* see dw-mipi-dsi.c */

What for ? :-)

+static const struct drm_bridge_funcs imx_nwl_dsi_bridge_funcs = {

• .pre_enable = imx_nwl_dsi_bridge_pre_enable,
• .disable = imx_nwl_dsi_bridge_disable,
• .mode_fixup = imx_nwl_dsi_bridge_mode_fixup,
• .mode_valid = imx_nwl_dsi_bridge_mode_valid,
• .attach = imx_nwl_dsi_bridge_attach,
• .detach = imx_nwl_dsi_bridge_detach,

+};

+static int imx_nwl_dsi_parse_dt(struct imx_nwl_dsi *dsi) +{

• struct device_node *np = dsi->dev->of_node;
• struct platform_device *pdev = to_platform_device(dsi->dev);
• struct resource *res;
• struct clk *clk;
• const char *clk_id;
• void __iomem *base;
• int i, ret;
• dsi->phy = devm_phy_get(dsi->dev, "dphy");
• if (IS_ERR(dsi->phy)) {

• ret = PTR_ERR(dsi->phy);
  

• dev_err(dsi->dev, "Could not get PHY (%d)\n", ret);
  

• return ret;
  

• }
• /* Platform dependent clocks */
• memcpy(dsi->clk_config, dsi->pdata->clk_config,

•       sizeof(dsi->pdata->clk_config));
  

• for (i = 0; i < ARRAY_SIZE(dsi->pdata->clk_config); i++) {

• if (!dsi->clk_config[i].present)
  

• 	continue;
  

• clk_id = dsi->clk_config[i].id;
  

• clk = devm_clk_get(dsi->dev, clk_id);
  

• if (IS_ERR(clk)) {
  

• 	ret = PTR_ERR(clk);
  

• 	dev_err(dsi->dev, "Failed to get %s clock (%d)\n",
  

• 		clk_id, ret);
  

• 	return ret;
  

• }
  

• DRM_DEV_DEBUG_DRIVER(dsi->dev, "Setup clk %s (rate: %lu)\n",
  

• 		     clk_id, clk_get_rate(clk));
  

• dsi->clk_config[i].clk = clk;
  

• }
• /* DSI clocks */
• clk = devm_clk_get(dsi->dev, "phy_ref");
• if (IS_ERR(clk)) {

• ret = PTR_ERR(clk);
  

• dev_err(dsi->dev, "Failed to get phy_ref clock: %d\n", ret);
  

• return ret;
  

• }
• dsi->phy_ref_clk = clk;
• clk = devm_clk_get(dsi->dev, "rx_esc");
• if (IS_ERR(clk)) {

• ret = PTR_ERR(clk);
  

• dev_err(dsi->dev, "Failed to get rx_esc clock: %d\n", ret);
  

• return ret;
  

• }
• dsi->rx_esc_clk = clk;
• clk = devm_clk_get(dsi->dev, "tx_esc");
• if (IS_ERR(clk)) {

• ret = PTR_ERR(clk);
  

• dev_err(dsi->dev, "Failed to get tx_esc clock: %d\n", ret);
  

• return ret;
  

• }
• dsi->tx_esc_clk = clk;
• dsi->csr = syscon_regmap_lookup_by_phandle(np, "csr");
• if (IS_ERR(dsi->csr) && dsi->pdata->ext_regs & IMX_REG_CSR) {

• ret = PTR_ERR(dsi->csr);
  

• DRM_DEV_ERROR(dsi->dev, "Failed to get CSR regmap: %d\n",
  

• 	      ret);
  

• return ret;
  

• }

This doesn't seem to be used anywhere.

• dsi->reset = syscon_regmap_lookup_by_phandle(np, "src");
• if (IS_ERR(dsi->reset) && (dsi->pdata->ext_regs & IMX_REG_SRC)) {

• ret = PTR_ERR(dsi->reset);
  

• DRM_DEV_ERROR(dsi->dev, "Failed to get SRC regmap: %d\n",
  

• 	      ret);
  

• return ret;
  

• }

Couldn't you model a reset controller in that syscon, and use the reset controller API here ? It would allow moving the i.MX-specific power on and off functions from this driver, making it more generic.

• dsi->mux_sel = syscon_regmap_lookup_by_phandle(np, "mux-sel");
• if (IS_ERR(dsi->mux_sel) && (dsi->pdata->ext_regs & IMX_REG_GPR)) {

• ret = PTR_ERR(dsi->mux_sel);
  

• DRM_DEV_ERROR(dsi->dev, "Failed to get GPR regmap: %d\n",
  

• 	      ret);
  

• return ret;
  

• }
• res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
• base = devm_ioremap_resource(dsi->dev, res);

You can replace those two calls with devm_platform_ioremap_resource().

• if (IS_ERR(base))

• return PTR_ERR(base);
  

• dsi->regmap =

• devm_regmap_init_mmio(dsi->dev, base, &nwl_dsi_regmap_config);
  

• if (IS_ERR(dsi->regmap)) {

• ret = PTR_ERR(dsi->regmap);
  

• DRM_DEV_ERROR(dsi->dev,
  

• 	      "Failed to create NWL DSI regmap: %d\n", ret);
  

• return ret;
  

• }
• dsi->irq = platform_get_irq(pdev, 0);
• if (dsi->irq < 0) {

• DRM_DEV_ERROR(dsi->dev, "Failed to get device IRQ: %d\n",
  

• 	      dsi->irq);
  

• return dsi->irq;
  

• }
• return 0;

+}

+static int imx8mq_dsi_poweron(struct imx_nwl_dsi *dsi) +{

• /* otherwise the display stays blank */
• usleep_range(200, 300);
• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, PCLK_RESET_N,

• 	   PCLK_RESET_N);
  

• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, ESC_RESET_N,

• 	   ESC_RESET_N);
  

• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, RESET_BYTE_N,

• 	   RESET_BYTE_N);
  

• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, DPI_RESET_N,

• 	   DPI_RESET_N);
  

• return 0;

+}

+static int imx8mq_dsi_poweroff(struct imx_nwl_dsi *dsi) +{

• if (USE_SRC_RESET_QUIRK(dsi->quirks))

• return 0;
  

• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, PCLK_RESET_N, 0);
• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, ESC_RESET_N, 0);
• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, RESET_BYTE_N, 0);
• regmap_update_bits(dsi->reset, SRC_MIPIPHY_RCR, DPI_RESET_N, 0);
• return 0;

+}

+static const struct drm_bridge_timings imx_nwl_timings = {

• .input_bus_flags = DRM_BUS_FLAG_DE_LOW,

+};

+static struct imx_nwl_platform_data imx8mq_dev = {

This structure should be const, especially as it contains function pointers.

• .poweron = &imx8mq_dsi_poweron,
• .poweroff = &imx8mq_dsi_poweroff,
• .clk_config = {

• { .id = CLK_CORE,   .present = true },
  

• { .id = CLK_PIXEL,  .present = false },
  

• { .id = CLK_BYPASS, .present = false },
  

• },
• .ext_regs = IMX_REG_SRC | IMX_REG_GPR,

+};

+static const struct of_device_id imx_nwl_dsi_dt_ids[] = {

• { .compatible = "fsl,imx8mq-nwl-dsi", .data = &imx8mq_dev, },
• { /* sentinel */ }

+}; +MODULE_DEVICE_TABLE(of, imx_nwl_dsi_dt_ids);

+static const struct soc_device_attribute imx_nwl_quirks_match[] = {

• { .soc_id = "i.MX8MQ", .revision = "2.0",

•  .data = (void *)(E11418_HS_MODE_QUIRK | SRC_RESET_QUIRK) },
  

• { /* sentinel. */ },

+};

+static int imx_nwl_dsi_probe(struct platform_device *pdev) +{

• struct device *dev = &pdev->dev;
• const struct of_device_id *of_id =

• of_match_device(imx_nwl_dsi_dt_ids, dev);
  

• const struct imx_nwl_platform_data *pdata = of_id->data;
• const struct soc_device_attribute *attr;
• struct imx_nwl_dsi *dsi;
• int ret;
• dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
• if (!dsi)

• return -ENOMEM;
  

• dsi->dev = dev;
• dsi->pdata = pdata;
• dsi->dpms_mode = DRM_MODE_DPMS_OFF;

DPMS is legacy, let's not use it within the driver.

• ret = imx_nwl_dsi_parse_dt(dsi);
• if (ret)

• return ret;
  

• ret = devm_request_irq(dev, dsi->irq, nwl_dsi_irq_handler, 0,

• 	       dev_name(dev), dsi);
  

• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to request IRQ: %d (%d)\n", dsi->irq,
  

• 	      ret);
  

• return ret;
  

• }
• dsi->dsi_host.ops = &nwl_dsi_host_ops;
• dsi->dsi_host.dev = dev;
• ret = mipi_dsi_host_register(&dsi->dsi_host);
• if (ret) {

• DRM_DEV_ERROR(dev, "Failed to register MIPI host: %d\n", ret);
  

• goto err_cleanup;
  

• }
• attr = soc_device_match(imx_nwl_quirks_match);
• if (attr)

• dsi->quirks = (uintptr_t)attr->data;
  

• dsi->bridge.driver_private = dsi;
• dsi->bridge.funcs = &imx_nwl_dsi_bridge_funcs;
• dsi->bridge.of_node = dev->of_node;
• dsi->bridge.timings = &imx_nwl_timings;
• drm_bridge_add(&dsi->bridge);
• dev_set_drvdata(dev, dsi);
• pm_runtime_enable(dev);
• return 0;

+err_cleanup:

• devm_free_irq(dev, dsi->irq, dsi);
• return ret;

+}

+static int imx_nwl_dsi_remove(struct platform_device *pdev) +{

• pm_runtime_disable(&pdev->dev);

You should call drm_bridge_remove() here, not in nwl_dsi_host_detach().

• return 0;

+}

+static struct platform_driver imx_nwl_dsi_driver = {

• .probe = imx_nwl_dsi_probe,
• .remove = imx_nwl_dsi_remove,
• .driver = {

• .of_match_table = imx_nwl_dsi_dt_ids,
  

• .name	= DRV_NAME,
  

• },

+};

+module_platform_driver(imx_nwl_dsi_driver);

+MODULE_AUTHOR("NXP Semiconductor"); +MODULE_AUTHOR("Purism SPC"); +MODULE_DESCRIPTION("i.MX8 Northwest Logic MIPI-DSI driver"); +MODULE_LICENSE("GPL"); /* GPLv2 or later */ diff --git a/drivers/gpu/drm/bridge/imx-nwl/nwl-drv.h b/drivers/gpu/drm/bridge/imx-nwl/nwl-drv.h new file mode 100644 index 000000000000..a1e30c58b627 --- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/nwl-drv.h @@ -0,0 +1,72 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/*

• • i.MX8 NWL MIPI DSI host driver
• • Copyright (C) 2017 NXP
• • Copyright (C) 2019 Purism SPC
• */

+#ifndef __NWL_DRV_H__ +#define __NWL_DRV_H__

+#include <drm/drm_mipi_dsi.h> +#include <linux/phy/phy.h>

+struct imx_nwl_platform_data;

+/* i.MX8 NWL quirks */ +/* i.MX8MQ errata E11418 */ +#define E11418_HS_MODE_QUIRK BIT(0) +#define USE_E11418_HS_MODE_QUIRK(x) ((x) & E11418_HS_MODE_QUIRK)

+/* Skip DSI bits in SRC on disable to avoid blank display on enable */ +#define SRC_RESET_QUIRK BIT(1) +#define USE_SRC_RESET_QUIRK(x) ((x) & SRC_RESET_QUIRK)

The USE_* macros are not shorter to type, so I would type out the & check explicitly.

+#define NWL_MAX_PLATFORM_CLOCKS 3 +struct imx_nwl_clk_config {

• const char *id;
• struct clk *clk;
• bool present;
• bool enabled;
• u32 rate;

+};

+struct imx_nwl_dsi {

• struct drm_bridge bridge;
• struct mipi_dsi_host dsi_host;
• struct drm_bridge *panel_bridge;
• struct device *dev;
• struct phy *phy;
• union phy_configure_opts phy_cfg;
• unsigned int quirks;
• struct regmap *regmap;
• int irq;
• /* External registers */
• struct regmap *csr;
• struct regmap *mux_sel;
• struct regmap *reset;
• /* Platform dependent clocks */
• struct imx_nwl_clk_config clk_config[3];

I would use NWL_MAX_PLATFORM_CLOCKS instead of 3 as imx_nwl_platform_data uses the macro.

• /* DSI clocks */
• struct clk *phy_ref_clk;
• struct clk *rx_esc_clk;
• struct clk *tx_esc_clk;
• /* dsi lanes */
• u32 lanes;
• enum mipi_dsi_pixel_format format;
• struct videomode vm;
• unsigned long dsi_mode_flags;
• int dpms_mode;
• struct mipi_dsi_transfer *xfer;
• const struct imx_nwl_platform_data *pdata;

+};

+#endif /* __NWL_DRV_H__ */ diff --git a/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c b/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c new file mode 100644 index 000000000000..0e1463af162f --- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.c @@ -0,0 +1,745 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • NWL DSI host driver
• • Copyright (C) 2017 NXP
• • Copyright (C) 2019 Purism SPC
• */

+#include <asm/unaligned.h> +#include <drm/drm_atomic_helper.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_of.h> +#include <drm/drm_panel.h> +#include <drm/drm_print.h> +#include <linux/clk.h> +#include <linux/irq.h> +#include <linux/regmap.h> +#include <video/mipi_display.h> +#include <video/videomode.h>

+#include "nwl-drv.h" +#include "nwl-dsi.h"

+#define MIPI_FIFO_TIMEOUT msecs_to_jiffies(500)

+/* PKT reg bit manipulation */ +#define REG_MASK(e, s) (((1 << ((e) - (s) + 1)) - 1) << (s)) +#define REG_PUT(x, e, s) (((x) << (s)) & REG_MASK(e, s)) +#define REG_GET(x, e, s) (((x) & REG_MASK(e, s)) >> (s))

Let's not reinvent the wheel, linux/bits.h and linux/bitfield.h can be used instead.

+/*

• • PKT_CONTROL format:
• • [15: 0] - word count
• • [17:16] - virtual channel
• • [23:18] - data type
• • [24] - LP or HS select (0 - LP, 1 - HS)
• • [25] - perform BTA after packet is sent
• • [26] - perform BTA only, no packet tx
• */

+#define WC(x) REG_PUT((x), 15, 0) +#define TX_VC(x) REG_PUT((x), 17, 16) +#define TX_DT(x) REG_PUT((x), 23, 18) +#define HS_SEL(x) REG_PUT((x), 24, 24) +#define BTA_TX(x) REG_PUT((x), 25, 25) +#define BTA_NO_TX(x) REG_PUT((x), 26, 26)

+/*

• • RX_PKT_HEADER format:
• • [15: 0] - word count
• • [21:16] - data type
• • [23:22] - virtual channel
• */

+#define RX_DT(x) REG_GET((x), 21, 16) +#define RX_VC(x) REG_GET((x), 23, 22)

+/*

• • DSI Video mode
• */

+#define VIDEO_MODE_BURST_MODE_WITH_SYNC_PULSES 0 +#define VIDEO_MODE_NON_BURST_MODE_WITH_SYNC_EVENTS BIT(0) +#define VIDEO_MODE_BURST_MODE BIT(1)

+/*

• • DPI color coding
• */

+#define DPI_16_BIT_565_PACKED 0 +#define DPI_16_BIT_565_ALIGNED 1 +#define DPI_16_BIT_565_SHIFTED 2 +#define DPI_18_BIT_PACKED 3 +#define DPI_18_BIT_ALIGNED 4 +#define DPI_24_BIT 5

+/*

• • DPI Pixel format
• */

+#define PIXEL_FORMAT_16 0 +#define PIXEL_FORMAT_18 BIT(0) +#define PIXEL_FORMAT_18L BIT(1) +#define PIXEL_FORMAT_24 (BIT(0) | BIT(1))

+enum transfer_direction { DSI_PACKET_SEND, DSI_PACKET_RECEIVE };

Line breaks please.

+struct mipi_dsi_transfer {

Let's not use such a generic name for a driver-specific structure. You should name is nwl_dsi_transfer.

• const struct mipi_dsi_msg *msg;
• struct mipi_dsi_packet packet;
• struct completion completed;
• int status; /* status of transmission */
• enum transfer_direction direction;
• bool need_bta;
• u8 cmd;
• u16 rx_word_count;
• size_t tx_len; /* bytes sent */
• size_t rx_len; /* bytes received */

+};

+static inline int nwl_dsi_write(struct imx_nwl_dsi *dsi, unsigned int reg,

• 		u32 val)
  

+{

• int ret;
• ret = regmap_write(dsi->regmap, reg, val);
• if (ret < 0)

• DRM_DEV_ERROR(dsi->dev,
  

• 	      "Failed to write NWL DSI reg 0x%x: %d\n", reg,
  

• 	      ret);
  

• return ret;

+}

+static inline u32 nwl_dsi_read(struct imx_nwl_dsi *dsi, u32 reg) +{

• unsigned int val;
• int ret;
• ret = regmap_read(dsi->regmap, reg, &val);
• if (ret < 0)

• DRM_DEV_ERROR(dsi->dev, "Failed to read NWL DSI reg 0x%x: %d\n",
  

• 	      reg, ret);
  

• return val;

You're loosing the error...

+}

+static u32 nwl_dsi_get_dpi_pixel_format(enum mipi_dsi_pixel_format format) +{

• switch (format) {
• case MIPI_DSI_FMT_RGB565:

• return PIXEL_FORMAT_16;
  

• case MIPI_DSI_FMT_RGB666:

• return PIXEL_FORMAT_18L;
  

• case MIPI_DSI_FMT_RGB666_PACKED:

• return PIXEL_FORMAT_18;
  

• case MIPI_DSI_FMT_RGB888:

• return PIXEL_FORMAT_24;
  

• default:

• return -EINVAL;
  

• }

+}

+int nwl_dsi_get_dphy_params(struct imx_nwl_dsi *dsi,

• 	    const struct drm_display_mode *mode,
  

• 	    union phy_configure_opts *phy_opts)
  

+{

• unsigned long rate;
• if (dsi->lanes < 1 || dsi->lanes > 4)

• return -EINVAL;
  

• /*

• * So far the DPHY spec minimal timings work for both mixel
  

• * dphy and nwl dsi host
  

• */
  

• phy_mipi_dphy_get_default_config(

• mode->crtc_clock * 1000,
  

• mipi_dsi_pixel_format_to_bpp(dsi->format), dsi->lanes,
  

• &phy_opts->mipi_dphy);
  

• rate = clk_get_rate(dsi->tx_esc_clk);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "LP clk is @%lu Hz\n", rate);
• phy_opts->mipi_dphy.lp_clk_rate = rate;
• return 0;

+} +EXPORT_SYMBOL_GPL(nwl_dsi_get_dphy_params);

No need to export symbols, those fubctions are only meant to be called from within the same module.

+#define PSEC_PER_SEC 1000000000000LL +/*

• • ps2bc - Picoseconds to byte clock cycles
• */

+static u32 ps2bc(struct imx_nwl_dsi *dsi, unsigned long long ps) +{

• int bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
• return DIV_ROUND_UP(ps * dsi->vm.pixelclock * bpp,

• 	    dsi->lanes * 8 * PSEC_PER_SEC);
  

+}

+/**

• • ui2bc - UI time periods to byte clock cycles
• */

+static u32 ui2bc(struct imx_nwl_dsi *dsi, unsigned long long ui) +{

• int bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
• return DIV_ROUND_UP(ui * dsi->lanes, dsi->vm.pixelclock * bpp);

+}

+#define USEC_PER_SEC 1000000L +/*

• • us2bc - micro seconds to lp clock cycles
• */

+static u32 us2lp(u32 lp_clk_rate, unsigned long us) +{

• return DIV_ROUND_UP(us * lp_clk_rate, USEC_PER_SEC);

+}

+static int nwl_dsi_config_host(struct imx_nwl_dsi *dsi) +{

• u32 cycles;
• struct phy_configure_opts_mipi_dphy *cfg = &dsi->phy_cfg.mipi_dphy;
• if (dsi->lanes < 1 || dsi->lanes > 4)

• return -EINVAL;
  

• DRM_DEV_DEBUG_DRIVER(dsi->dev, "DSI Lanes %d\n", dsi->lanes);
• nwl_dsi_write(dsi, CFG_NUM_LANES, dsi->lanes - 1);
• if (dsi->dsi_mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {

• nwl_dsi_write(dsi, CFG_NONCONTINUOUS_CLK, 0x01);
  

• nwl_dsi_write(dsi, CFG_AUTOINSERT_EOTP, 0x01);
  

• } else {

• nwl_dsi_write(dsi, CFG_NONCONTINUOUS_CLK, 0x00);
  

• nwl_dsi_write(dsi, CFG_AUTOINSERT_EOTP, 0x00);
  

• }
• /* values in byte clock cycles */
• cycles = ui2bc(dsi, cfg->clk_pre);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_t_pre: 0x%x\n", cycles);
• nwl_dsi_write(dsi, CFG_T_PRE, cycles);
• cycles = ps2bc(dsi, cfg->lpx + cfg->clk_prepare + cfg->clk_zero);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap (pre): 0x%x\n", cycles);
• cycles += ui2bc(dsi, cfg->clk_pre);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap: 0x%x\n", cycles);
• nwl_dsi_write(dsi, CFG_T_POST, cycles);
• cycles = ps2bc(dsi, cfg->hs_exit);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap: 0x%x\n", cycles);
• nwl_dsi_write(dsi, CFG_TX_GAP, cycles);
• nwl_dsi_write(dsi, CFG_EXTRA_CMDS_AFTER_EOTP, 0x01);
• nwl_dsi_write(dsi, CFG_HTX_TO_COUNT, 0x00);
• nwl_dsi_write(dsi, CFG_LRX_H_TO_COUNT, 0x00);
• nwl_dsi_write(dsi, CFG_BTA_H_TO_COUNT, 0x00);
• /* In LP clock cycles */
• cycles = us2lp(cfg->lp_clk_rate, cfg->wakeup);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_twakeup: 0x%x\n", cycles);
• nwl_dsi_write(dsi, CFG_TWAKEUP, cycles);
• return 0;

+}

+static int nwl_dsi_config_dpi(struct imx_nwl_dsi *dsi) +{

• struct videomode *vm = &dsi->vm;
• u32 color_format, mode;
• bool burst_mode;
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "hfront_porch = %d\n", vm->hfront_porch);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "hback_porch = %d\n", vm->hback_porch);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "hsync_len = %d\n", vm->hsync_len);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "hactive = %d\n", vm->hactive);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "vfront_porch = %d\n", vm->vfront_porch);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "vback_porch = %d\n", vm->vback_porch);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "vsync_len = %d\n", vm->vsync_len);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "vactive = %d\n", vm->vactive);
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "clock = %lu kHz\n",

• 	     vm->pixelclock / 1000);
  

• color_format = nwl_dsi_get_dpi_pixel_format(dsi->format);
• if (color_format < 0) {

• DRM_DEV_ERROR(dsi->dev, "Invalid color format 0x%x\n",
  

• 	      dsi->format);
  

• return color_format;
  

• }
• DRM_DEV_DEBUG_DRIVER(dsi->dev, "pixel fmt = %d\n", dsi->format);
• nwl_dsi_write(dsi, INTERFACE_COLOR_CODING, DPI_24_BIT);
• nwl_dsi_write(dsi, PIXEL_FORMAT, color_format);
• /*

• * Adjusting input polarity based on the video mode results in
  

• * a black screen so always pick active low:
  

• */
  

• nwl_dsi_write(dsi, VSYNC_POLARITY, VSYNC_POLARITY_ACTIVE_LOW);
• nwl_dsi_write(dsi, HSYNC_POLARITY, HSYNC_POLARITY_ACTIVE_LOW);
• burst_mode = (dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_BURST) &&

•      !(dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE);
  

• if (burst_mode) {

• nwl_dsi_write(dsi, VIDEO_MODE, VIDEO_MODE_BURST_MODE);
  

• nwl_dsi_write(dsi, PIXEL_FIFO_SEND_LEVEL, 256);
  

• } else {

• mode = ((dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) ?
  

• 		VIDEO_MODE_BURST_MODE_WITH_SYNC_PULSES :
  

• 		VIDEO_MODE_NON_BURST_MODE_WITH_SYNC_EVENTS);
  

• nwl_dsi_write(dsi, VIDEO_MODE, mode);
  

• nwl_dsi_write(dsi, PIXEL_FIFO_SEND_LEVEL, vm->hactive);
  

• }
• nwl_dsi_write(dsi, HFP, vm->hfront_porch);
• nwl_dsi_write(dsi, HBP, vm->hback_porch);
• nwl_dsi_write(dsi, HSA, vm->hsync_len);
• nwl_dsi_write(dsi, ENABLE_MULT_PKTS, 0x0);
• nwl_dsi_write(dsi, BLLP_MODE, 0x1);
• nwl_dsi_write(dsi, ENABLE_MULT_PKTS, 0x0);
• nwl_dsi_write(dsi, USE_NULL_PKT_BLLP, 0x0);
• nwl_dsi_write(dsi, VC, 0x0);
• nwl_dsi_write(dsi, PIXEL_PAYLOAD_SIZE, vm->hactive);
• nwl_dsi_write(dsi, VACTIVE, vm->vactive - 1);
• nwl_dsi_write(dsi, VBP, vm->vback_porch);
• nwl_dsi_write(dsi, VFP, vm->vfront_porch);
• return 0;

+}

+static int nwl_dsi_enable_tx_clock(struct imx_nwl_dsi *dsi) +{

• struct device *dev = dsi->dev;
• int ret;
• ret = clk_prepare_enable(dsi->tx_esc_clk);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to enable tx_esc clk: %d\n", ret);
  

• return ret;
  

• }
• DRM_DEV_DEBUG_DRIVER(dev, "Enabled tx_esc clk @%lu Hz\n",

• 	     clk_get_rate(dsi->tx_esc_clk));
  

• return 0;

+}

+static int nwl_dsi_enable_rx_clock(struct imx_nwl_dsi *dsi) +{

• struct device *dev = dsi->dev;
• int ret;
• ret = clk_prepare_enable(dsi->rx_esc_clk);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to enable rx_esc clk: %d\n", ret);
  

• return ret;
  

• }
• DRM_DEV_DEBUG_DRIVER(dev, "Enabled rx_esc clk @%lu Hz\n",

• 	     clk_get_rate(dsi->rx_esc_clk));
  

• return 0;

+}

+static void nwl_dsi_init_interrupts(struct imx_nwl_dsi *dsi) +{

• u32 irq_enable;
• nwl_dsi_write(dsi, IRQ_MASK, 0xffffffff);
• nwl_dsi_write(dsi, IRQ_MASK2, 0x7);
• irq_enable = ~(u32)(TX_PKT_DONE_MASK | RX_PKT_HDR_RCVD_MASK |

• 	    TX_FIFO_OVFLW_MASK | HS_TX_TIMEOUT_MASK);
  

• nwl_dsi_write(dsi, IRQ_MASK, irq_enable);

+}

+static int nwl_dsi_host_attach(struct mipi_dsi_host *dsi_host,

• 	       struct mipi_dsi_device *device)
  

+{

• struct imx_nwl_dsi *dsi =

• container_of(dsi_host, struct imx_nwl_dsi, dsi_host);
  

• struct device *dev = dsi->dev;
• struct drm_bridge *bridge;
• struct drm_panel *panel;
• int ret;
• DRM_DEV_INFO(dev, "lanes=%u, format=0x%x flags=0x%lx\n", device->lanes,

•      device->format, device->mode_flags);
  

• if (device->lanes < 1 || device->lanes > 4)

• return -EINVAL;
  

• dsi->lanes = device->lanes;
• dsi->format = device->format;
• dsi->dsi_mode_flags = device->mode_flags;
• ret = drm_of_find_panel_or_bridge(dsi->dev->of_node, 1, 0, &panel,

• 			  &bridge);
  

• if (ret)

• return ret;
  

• if (panel) {

• bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DSI);
  

• if (IS_ERR(bridge))
  

• 	return PTR_ERR(bridge);
  

• }
• dsi->panel_bridge = bridge;
• drm_bridge_add(&dsi->bridge);
• return 0;

+}

+static int nwl_dsi_host_detach(struct mipi_dsi_host *dsi_host,

• 	       struct mipi_dsi_device *device)
  

+{

• struct imx_nwl_dsi *dsi =

• container_of(dsi_host, struct imx_nwl_dsi, dsi_host);
  

• drm_of_panel_bridge_remove(dsi->dev->of_node, 1, 0);
• drm_bridge_remove(&dsi->bridge);
• return 0;

+}

+static bool nwl_dsi_read_packet(struct imx_nwl_dsi *dsi, u32 status) +{

• struct device *dev = dsi->dev;
• struct mipi_dsi_transfer *xfer = dsi->xfer;
• u8 *payload = xfer->msg->rx_buf;
• u32 val;
• u16 word_count;
• u8 channel;
• u8 data_type;
• xfer->status = 0;
• if (xfer->rx_word_count == 0) {

• if (!(status & RX_PKT_HDR_RCVD))
  

• 	return false;
  

• /* Get the RX header and parse it */
  

• val = nwl_dsi_read(dsi, RX_PKT_HEADER);
  

• word_count = WC(val);
  

• channel = RX_VC(val);
  

• data_type = RX_DT(val);
  

• if (channel != xfer->msg->channel) {
  

• 	DRM_DEV_ERROR(dev,
  

• 		      "[%02X] Channel mismatch (%u != %u)\n",
  

• 		      xfer->cmd, channel, xfer->msg->channel);
  

• 	return true;
  

• }
  

• switch (data_type) {
  

• case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_2BYTE:
  

• 	/* Fall through */
  

• case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
  

• 	if (xfer->msg->rx_len > 1) {
  

• 		/* read second byte */
  

• 		payload[1] = word_count >> 8;
  

• 		++xfer->rx_len;
  

• 	}
  

• 	/* Fall through */
  

• case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
  

• 	/* Fall through */
  

• case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
  

• 	if (xfer->msg->rx_len > 0) {
  

• 		/* read first byte */
  

• 		payload[0] = word_count & 0xff;
  

• 		++xfer->rx_len;
  

• 	}
  

• 	xfer->status = xfer->rx_len;
  

• 	return true;
  

• case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
  

• 	word_count &= 0xff;
  

• 	DRM_DEV_ERROR(dev, "[%02X] DSI error report: 0x%02x\n",
  

• 		      xfer->cmd, word_count);
  

• 	xfer->status = -EPROTO;
  

• 	return true;
  

• }
  

• if (word_count > xfer->msg->rx_len) {
  

• 	DRM_DEV_ERROR(
  

• 		dev,
  

• 		"[%02X] Receive buffer too small: %lu (< %u)\n",
  

• 		xfer->cmd, xfer->msg->rx_len, word_count);
  

• 	return true;
  

• }
  

• xfer->rx_word_count = word_count;
  

• } else {

• /* Set word_count from previous header read */
  

• word_count = xfer->rx_word_count;
  

• }
• /* If RX payload is not yet received, wait for it */
• if (!(status & RX_PKT_PAYLOAD_DATA_RCVD))

• return false;
  

• /* Read the RX payload */
• while (word_count >= 4) {

• val = nwl_dsi_read(dsi, RX_PAYLOAD);
  

• payload[0] = (val >> 0) & 0xff;
  

• payload[1] = (val >> 8) & 0xff;
  

• payload[2] = (val >> 16) & 0xff;
  

• payload[3] = (val >> 24) & 0xff;
  

• payload += 4;
  

• xfer->rx_len += 4;
  

• word_count -= 4;
  

• }
• if (word_count > 0) {

• val = nwl_dsi_read(dsi, RX_PAYLOAD);
  

• switch (word_count) {
  

• case 3:
  

• 	payload[2] = (val >> 16) & 0xff;
  

• 	++xfer->rx_len;
  

• 	/* Fall through */
  

• case 2:
  

• 	payload[1] = (val >> 8) & 0xff;
  

• 	++xfer->rx_len;
  

• 	/* Fall through */
  

• case 1:
  

• 	payload[0] = (val >> 0) & 0xff;
  

• 	++xfer->rx_len;
  

• 	break;
  

• }
  

• }
• xfer->status = xfer->rx_len;
• return true;

+}

+static void nwl_dsi_finish_transmission(struct imx_nwl_dsi *dsi, u32 status) +{

• struct mipi_dsi_transfer *xfer = dsi->xfer;
• bool end_packet = false;
• if (!xfer)

• return;
  

• if (status & TX_FIFO_OVFLW) {

• DRM_DEV_ERROR_RATELIMITED(dsi->dev, "tx fifo overflow\n");
  

• return;
  

• }
• if (status & HS_TX_TIMEOUT) {

• DRM_DEV_ERROR_RATELIMITED(dsi->dev, "HS tx timeout\n");
  

• return;
  

• }
• if (xfer->direction == DSI_PACKET_SEND && status & TX_PKT_DONE) {

• xfer->status = xfer->tx_len;
  

• end_packet = true;
  

• } else if (status & DPHY_DIRECTION &&

•    ((status & (RX_PKT_HDR_RCVD | RX_PKT_PAYLOAD_DATA_RCVD)))) {
  

• end_packet = nwl_dsi_read_packet(dsi, status);
  

• }
• if (end_packet)

• complete(&xfer->completed);
  

+}

+static void nwl_dsi_begin_transmission(struct imx_nwl_dsi *dsi) +{

• struct mipi_dsi_transfer *xfer = dsi->xfer;
• struct mipi_dsi_packet *pkt = &xfer->packet;
• const u8 *payload;
• size_t length;
• u16 word_count;
• u8 hs_mode;
• u32 val;
• u32 hs_workaround = 0;
• /* Send the payload, if any */
• length = pkt->payload_length;
• payload = pkt->payload;
• while (length >= 4) {

• val = get_unaligned_le32(payload);
  

The framework doesn't guarantee the payload to be aligned on a multiple of 4 bytes ?

• hs_workaround |= !(val & 0xFFFF00);
  

• nwl_dsi_write(dsi, TX_PAYLOAD, val);
  

• payload += 4;
  

• length -= 4;
  

• }
• /* Send the rest of the payload */
• val = 0;
• switch (length) {
• case 3:

• val |= payload[2] << 16;
  

• /* Fall through */
  

• case 2:

• val |= payload[1] << 8;
  

• hs_workaround |= !(val & 0xFFFF00);
  

• /* Fall through */
  

• case 1:

• val |= payload[0];
  

• nwl_dsi_write(dsi, TX_PAYLOAD, val);
  

• break;
  

• }
• xfer->tx_len = pkt->payload_length;
• /*

• * Send the header
  

• * header[0] = Virtual Channel + Data Type
  

• * header[1] = Word Count LSB (LP) or first param (SP)
  

• * header[2] = Word Count MSB (LP) or second param (SP)
  

• */
  

• word_count = pkt->header[1] | (pkt->header[2] << 8);
• if ((hs_workaround && USE_E11418_HS_MODE_QUIRK(dsi->quirks))) {

• DRM_DEV_DEBUG_DRIVER(dsi->dev,
  

• 		     "Using hs mode workaround for cmd 0x%x\n",
  

• 		     xfer->cmd);
  

• hs_mode = 1;
  

• } else {

• hs_mode = (xfer->msg->flags & MIPI_DSI_MSG_USE_LPM) ? 0 : 1;
  

• }
• val = WC(word_count) |

• TX_VC(xfer->msg->channel) |
  

• TX_DT(xfer->msg->type) |
  

• HS_SEL(hs_mode) |
  

• BTA_TX(xfer->need_bta);
  

• nwl_dsi_write(dsi, PKT_CONTROL, val);
• /* Send packet command */
• nwl_dsi_write(dsi, SEND_PACKET, 0x1);

+}

+static ssize_t nwl_dsi_host_transfer(struct mipi_dsi_host *dsi_host,

• 		     const struct mipi_dsi_msg *msg)
  

+{

• struct imx_nwl_dsi *dsi =

• container_of(dsi_host, struct imx_nwl_dsi, dsi_host);
  

• struct mipi_dsi_transfer xfer;
• ssize_t ret = 0;
• /* Create packet to be sent */
• dsi->xfer = &xfer;
• ret = mipi_dsi_create_packet(&xfer.packet, msg);
• if (ret < 0) {

• dsi->xfer = NULL;
  

• return ret;
  

• }
• if ((msg->type & MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM ||

•     msg->type & MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM ||
  

•     msg->type & MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM ||
  

•     msg->type & MIPI_DSI_DCS_READ) &&
  

•    msg->rx_len > 0 && msg->rx_buf != NULL)
  

• xfer.direction = DSI_PACKET_RECEIVE;
  

• else

• xfer.direction = DSI_PACKET_SEND;
  

• xfer.need_bta = (xfer.direction == DSI_PACKET_RECEIVE);
• xfer.need_bta |= (msg->flags & MIPI_DSI_MSG_REQ_ACK) ? 1 : 0;
• xfer.msg = msg;
• xfer.status = -ETIMEDOUT;
• xfer.rx_word_count = 0;
• xfer.rx_len = 0;
• xfer.cmd = 0x00;
• if (msg->tx_len > 0)

• xfer.cmd = ((u8 *)(msg->tx_buf))[0];
  

• init_completion(&xfer.completed);
• nwl_dsi_enable_rx_clock(dsi);
• /* Initiate the DSI packet transmision */
• nwl_dsi_begin_transmission(dsi);
• if (!wait_for_completion_timeout(&xfer.completed, MIPI_FIFO_TIMEOUT)) {

• DRM_DEV_ERROR(dsi_host->dev, "[%02X] DSI transfer timed out\n",
  

• 	      xfer.cmd);
  

• ret = -ETIMEDOUT;
  

• } else {

• ret = xfer.status;
  

• }
• clk_disable_unprepare(dsi->rx_esc_clk);
• return ret;

+}

+const struct mipi_dsi_host_ops nwl_dsi_host_ops = {

• .attach = nwl_dsi_host_attach,
• .detach = nwl_dsi_host_detach,
• .transfer = nwl_dsi_host_transfer,

+};

+irqreturn_t nwl_dsi_irq_handler(int irq, void *data) +{

• u32 irq_status;
• struct imx_nwl_dsi *dsi = data;
• irq_status = nwl_dsi_read(dsi, IRQ_STATUS);
• if (irq_status & TX_PKT_DONE || irq_status & RX_PKT_HDR_RCVD ||

•    irq_status & RX_PKT_PAYLOAD_DATA_RCVD)
  

• nwl_dsi_finish_transmission(dsi, irq_status);
  

• return IRQ_HANDLED;

+} +EXPORT_SYMBOL_GPL(nwl_dsi_irq_handler);

+int nwl_dsi_enable(struct imx_nwl_dsi *dsi) +{

• struct device *dev = dsi->dev;
• union phy_configure_opts *phy_cfg = &dsi->phy_cfg;
• int ret;
• if (!dsi->lanes) {

• DRM_DEV_ERROR(dev, "Need DSI lanes: %d\n", dsi->lanes);
  

• return -EINVAL;
  

• }
• ret = phy_init(dsi->phy);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to init DSI phy: %d\n", ret);
  

• return ret;
  

• }
• ret = phy_configure(dsi->phy, phy_cfg);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to configure DSI phy: %d\n", ret);
  

• return ret;
  

• }
• ret = nwl_dsi_enable_tx_clock(dsi);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to enable tx clock: %d\n", ret);
  

• return ret;
  

• }
• ret = nwl_dsi_config_host(dsi);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to set up DSI: %d", ret);
  

• return ret;
  

• }
• ret = nwl_dsi_config_dpi(dsi);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to set up DPI: %d", ret);
  

• return ret;
  

• }
• ret = phy_power_on(dsi->phy);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "Failed to power on DPHY (%d)\n", ret);
  

• return ret;
  

• }
• nwl_dsi_init_interrupts(dsi);
• return 0;

+} +EXPORT_SYMBOL_GPL(nwl_dsi_enable);

+int nwl_dsi_disable(struct imx_nwl_dsi *dsi) +{

• struct device *dev = dsi->dev;
• DRM_DEV_DEBUG_DRIVER(dev, "Disabling clocks and phy\n");
• phy_power_off(dsi->phy);
• phy_exit(dsi->phy);
• /* Disabling the clock before the phy breaks enabling dsi again */
• clk_disable_unprepare(dsi->tx_esc_clk);
• return 0;

+} +EXPORT_SYMBOL_GPL(nwl_dsi_disable); diff --git a/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.h b/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.h new file mode 100644 index 000000000000..7bcf804843e2 --- /dev/null +++ b/drivers/gpu/drm/bridge/imx-nwl/nwl-dsi.h @@ -0,0 +1,111 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/*

• • i.MX8 NWL MIPI DSI host driver
• • Copyright (C) 2017 NXP
• • Copyright (C) 2019 Purism SPC
• */

+#ifndef __NWL_DSI_H__ +#define __NWL_DSI_H__

+#include <drm/drm_mipi_dsi.h>

+/* DSI HOST registers */ +#define CFG_NUM_LANES 0x0

Some of the register names are quite prone to namespace clashes. I recommend prefixing them all with NWL_DSI_.

+#define CFG_NONCONTINUOUS_CLK 0x4 +#define CFG_T_PRE 0x8 +#define CFG_T_POST 0xc +#define CFG_TX_GAP 0x10 +#define CFG_AUTOINSERT_EOTP 0x14 +#define CFG_EXTRA_CMDS_AFTER_EOTP 0x18 +#define CFG_HTX_TO_COUNT 0x1c +#define CFG_LRX_H_TO_COUNT 0x20 +#define CFG_BTA_H_TO_COUNT 0x24 +#define CFG_TWAKEUP 0x28 +#define CFG_STATUS_OUT 0x2c +#define RX_ERROR_STATUS 0x30

+/* DSI DPI registers */ +#define PIXEL_PAYLOAD_SIZE 0x200 +#define PIXEL_FIFO_SEND_LEVEL 0x204 +#define INTERFACE_COLOR_CODING 0x208 +#define PIXEL_FORMAT 0x20c +#define VSYNC_POLARITY 0x210 +#define VSYNC_POLARITY_ACTIVE_LOW 0 +#define VSYNC_POLARITY_ACTIVE_HIGH BIT(1)

+#define HSYNC_POLARITY 0x214 +#define HSYNC_POLARITY_ACTIVE_LOW 0 +#define HSYNC_POLARITY_ACTIVE_HIGH BIT(1)

+#define VIDEO_MODE 0x218 +#define HFP 0x21c +#define HBP 0x220 +#define HSA 0x224 +#define ENABLE_MULT_PKTS 0x228 +#define VBP 0x22c +#define VFP 0x230 +#define BLLP_MODE 0x234 +#define USE_NULL_PKT_BLLP 0x238 +#define VACTIVE 0x23c +#define VC 0x240

+/* DSI APB PKT control */ +#define TX_PAYLOAD 0x280 +#define PKT_CONTROL 0x284 +#define SEND_PACKET 0x288 +#define PKT_STATUS 0x28c +#define PKT_FIFO_WR_LEVEL 0x290 +#define PKT_FIFO_RD_LEVEL 0x294 +#define RX_PAYLOAD 0x298 +#define RX_PKT_HEADER 0x29c

+/* DSI IRQ handling */ +#define IRQ_STATUS 0x2a0 +#define SM_NOT_IDLE BIT(0) +#define TX_PKT_DONE BIT(1) +#define DPHY_DIRECTION BIT(2) +#define TX_FIFO_OVFLW BIT(3) +#define TX_FIFO_UDFLW BIT(4) +#define RX_FIFO_OVFLW BIT(5) +#define RX_FIFO_UDFLW BIT(6) +#define RX_PKT_HDR_RCVD BIT(7) +#define RX_PKT_PAYLOAD_DATA_RCVD BIT(8) +#define BTA_TIMEOUT BIT(29) +#define LP_RX_TIMEOUT BIT(30) +#define HS_TX_TIMEOUT BIT(31)

+#define IRQ_STATUS2 0x2a4 +#define SINGLE_BIT_ECC_ERR BIT(0) +#define MULTI_BIT_ECC_ERR BIT(1) +#define CRC_ERR BIT(2)

+#define IRQ_MASK 0x2a8 +#define SM_NOT_IDLE_MASK BIT(0) +#define TX_PKT_DONE_MASK BIT(1) +#define DPHY_DIRECTION_MASK BIT(2) +#define TX_FIFO_OVFLW_MASK BIT(3) +#define TX_FIFO_UDFLW_MASK BIT(4) +#define RX_FIFO_OVFLW_MASK BIT(5) +#define RX_FIFO_UDFLW_MASK BIT(6) +#define RX_PKT_HDR_RCVD_MASK BIT(7) +#define RX_PKT_PAYLOAD_DATA_RCVD_MASK BIT(8) +#define BTA_TIMEOUT_MASK BIT(29) +#define LP_RX_TIMEOUT_MASK BIT(30) +#define HS_TX_TIMEOUT_MASK BIT(31)

+#define IRQ_MASK2 0x2ac +#define SINGLE_BIT_ECC_ERR_MASK BIT(0) +#define MULTI_BIT_ECC_ERR_MASK BIT(1) +#define CRC_ERR_MASK BIT(2)

+extern const struct mipi_dsi_host_ops nwl_dsi_host_ops;

+irqreturn_t nwl_dsi_irq_handler(int irq, void *data); +int nwl_dsi_enable(struct imx_nwl_dsi *dsi); +int nwl_dsi_disable(struct imx_nwl_dsi *dsi); +int nwl_dsi_get_dphy_params(struct imx_nwl_dsi *dsi,

• 	    const struct drm_display_mode *mode,
  

• 	    union phy_configure_opts *phy_opts);
  

+#endif /* __NWL_DSI_H__ */