Re: [PATCH v3 10/14] drm: rcar-du: kms: Collect CMM instances

Hi Jacopo,

Thank you for the patch.

On Sun, Aug 25, 2019 at 03:51:50PM +0200, Jacopo Mondi wrote:

Implement device tree parsing to collect the available CMM instances described by the 'cmms' property. Associate CMMs with CRTCs and store a mask of active CMMs in the DU group for later enablement.

Enforce the suspend/resume ordering of DU and CMM by creating a stateless device link between the two to make sure the CMM supplier device suspends after and resumes before the DU consumer.

Signed-off-by: Jacopo Mondi jacopo+renesas@jmondi.org

drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 6 +++ drivers/gpu/drm/rcar-du/rcar_du_crtc.h | 2 + drivers/gpu/drm/rcar-du/rcar_du_drv.h | 3 ++ drivers/gpu/drm/rcar-du/rcar_du_group.h | 2 + drivers/gpu/drm/rcar-du/rcar_du_kms.c | 63 +++++++++++++++++++++++++ 5 files changed, 76 insertions(+)

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index 2da46e3dc4ae..23f1d6cc1719 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -1194,6 +1194,12 @@ int rcar_du_crtc_create(struct rcar_du_group *rgrp, unsigned int swindex, if (ret < 0) return ret;

• /* CMM might be disabled for this CRTC. */

• if (rcdu->cmms[swindex]) {

• rcrtc->cmm = rcdu->cmms[swindex];
  

• rgrp->cmms_mask |= BIT(hwindex % 2);
  

• }

• drm_crtc_helper_add(crtc, &crtc_helper_funcs);

  /* Start with vertical blanking interrupt reporting disabled. */

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h index 3b7fc668996f..5f2940c42225 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h @@ -39,6 +39,7 @@ struct rcar_du_vsp;

• @vblank_wait: wait queue used to signal vertical blanking
• @vblank_count: number of vertical blanking interrupts to wait for
• @group: CRTC group this CRTC belongs to

• • @cmm: CMM associated with this CRTC
  • @vsp: VSP feeding video to this CRTC
  • @vsp_pipe: index of the VSP pipeline feeding video to this CRTC
  • @writeback: the writeback connector

@@ -64,6 +65,7 @@ struct rcar_du_crtc { unsigned int vblank_count;

struct rcar_du_group *group;

• struct platform_device *cmm; struct rcar_du_vsp *vsp; unsigned int vsp_pipe;

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.h b/drivers/gpu/drm/rcar-du/rcar_du_drv.h index a00dccc447aa..300ec60ba31b 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_drv.h +++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.h @@ -13,6 +13,7 @@ #include <linux/kernel.h> #include <linux/wait.h>

+#include "rcar_cmm.h" #include "rcar_du_crtc.h" #include "rcar_du_group.h" #include "rcar_du_vsp.h" @@ -70,6 +71,7 @@ struct rcar_du_device_info {

#define RCAR_DU_MAX_CRTCS 4 #define RCAR_DU_MAX_GROUPS DIV_ROUND_UP(RCAR_DU_MAX_CRTCS, 2) +#define RCAR_DU_MAX_CMMS 4

Maybe alphabetically sorted ?

#define RCAR_DU_MAX_VSPS 4

struct rcar_du_device { @@ -86,6 +88,7 @@ struct rcar_du_device { struct rcar_du_encoder *encoders[RCAR_DU_OUTPUT_MAX];

struct rcar_du_group groups[RCAR_DU_MAX_GROUPS];

• struct platform_device *cmms[RCAR_DU_MAX_CMMS];

As there's one CMM per CRTC, should we use RCAR_DU_MAX_CRTCS here ? It's not very useful to have two different macros that are required to have the same value :-)

struct rcar_du_vsp vsps[RCAR_DU_MAX_VSPS];

struct { diff --git a/drivers/gpu/drm/rcar-du/rcar_du_group.h b/drivers/gpu/drm/rcar-du/rcar_du_group.h index 87950c1f6a52..e9906609c635 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_group.h +++ b/drivers/gpu/drm/rcar-du/rcar_du_group.h @@ -22,6 +22,7 @@ struct rcar_du_device;

• @mmio_offset: registers offset in the device memory map
• @index: group index
• @channels_mask: bitmask of populated DU channels in this group

• • @cmms_mask: bitmask of available CMMs in this group
  • @num_crtcs: number of CRTCs in this group (1 or 2)
  • @use_count: number of users of the group (rcar_du_group_(get|put))
  • @used_crtcs: number of CRTCs currently in use

@@ -37,6 +38,7 @@ struct rcar_du_group { unsigned int index;

unsigned int channels_mask;

• unsigned int cmms_mask; unsigned int num_crtcs; unsigned int use_count; unsigned int used_crtcs;

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_kms.c b/drivers/gpu/drm/rcar-du/rcar_du_kms.c index 2dc9caee8767..61ca1d3c379a 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_kms.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_kms.c @@ -17,7 +17,9 @@ #include <drm/drm_probe_helper.h> #include <drm/drm_vblank.h>

+#include <linux/device.h> #include <linux/of_graph.h> +#include <linux/of_platform.h> #include <linux/wait.h>

#include "rcar_du_crtc.h" @@ -614,6 +616,62 @@ static int rcar_du_vsps_init(struct rcar_du_device *rcdu) return ret; }

+static int rcar_du_cmm_init(struct rcar_du_device *rcdu) +{

• const struct device_node *np = rcdu->dev->of_node;
• unsigned int i;
• int cells;
• cells = of_property_count_u32_elems(np, "cmms");
• if (cells == -EINVAL)

• return 0;
  

• if (cells > RCAR_DU_MAX_CMMS || cells > rcdu->num_crtcs) {

And if we remove RCAR_DU_MAX_CMMS as proposed above, I would just remove the first part of the condition, as rcdu->num_crtcs is guaranteed to be <= RCAR_DU_MAX_CRTCS.

With this addressed,

Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com

• dev_err(rcdu->dev,
  

• 	"Invalid number of entries in 'cmms' property\n");
  

• return -EINVAL;
  

• }
• for (i = 0; i < cells; ++i) {

• struct platform_device *pdev;
  

• struct device_link *link;
  

• struct device_node *cmm;
  

• cmm = of_parse_phandle(np, "cmms", i);
  

• if (IS_ERR(cmm)) {
  

• 	dev_err(rcdu->dev, "Failed to parse 'cmms' property\n");
  

• 	return PTR_ERR(cmm);
  

• }
  

• if (!of_device_is_available(cmm)) {
  

• 	/* It's fine to have a phandle to a non-enabled CMM. */
  

• 	of_node_put(cmm);
  

• 	continue;
  

• }
  

• pdev = of_find_device_by_node(cmm);
  

• if (IS_ERR(pdev)) {
  

• 	dev_err(rcdu->dev, "No device found for CMM%u\n", i);
  

• 	of_node_put(cmm);
  

• 	return PTR_ERR(pdev);
  

• }
  

• of_node_put(cmm);
  

• link = device_link_add(rcdu->dev, &pdev->dev,
  

• 		       DL_FLAG_STATELESS);
  

• if (!link) {
  

• 	dev_err(rcdu->dev,
  

• 		"Failed to create device link to CMM%u\n", i);
  

• 	return -EINVAL;
  

• }
  

• rcdu->cmms[i] = pdev;
  

• }
• return 0;

+}

int rcar_du_modeset_init(struct rcar_du_device *rcdu) { static const unsigned int mmio_offsets[] = { @@ -704,6 +762,11 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu) return ret; }

• /* Initialize the Color Management Modules. */
• ret = rcar_du_cmm_init(rcdu);
• if (ret)

• return ret;
  

• /* Create the CRTCs. */ for (swindex = 0, hwindex = 0; swindex < rcdu->num_crtcs; ++hwindex) { struct rcar_du_group *rgrp;