Revision 1 of the IP doesn't work if we don't load the palette (even if it's not used, which is the case for the RGB565 format).

Add a function called from tilcdc_crtc_enable() which performs all required actions if we're dealing with a rev1 chip.

Signed-off-by: Bartosz Golaszewski bgolaszewski@baylibre.com --- v1 -> v2: - only allocate dma memory for revision 1

v2 -> v3: - use devres managed API for dma memory allocation

drivers/gpu/drm/tilcdc/tilcdc_crtc.c | 81 +++++++++++++++++++++++++++++++++++- 1 file changed, 80 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c index 87cfde9..bc77b73 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c @@ -21,11 +21,15 @@ #include <drm/drm_flip_work.h> #include <drm/drm_plane_helper.h> #include <linux/workqueue.h> +#include <linux/completion.h> +#include <linux/dma-mapping.h>

#include "tilcdc_drv.h" #include "tilcdc_regs.h"

-#define TILCDC_VBLANK_SAFETY_THRESHOLD_US 1000 +#define TILCDC_VBLANK_SAFETY_THRESHOLD_US 1000 +#define TILCDC_REV1_PALETTE_SIZE 32 +#define TILCDC_REV1_PALETTE_FIRST_ENTRY 0x4000

struct tilcdc_crtc { struct drm_crtc base; @@ -53,6 +57,10 @@ struct tilcdc_crtc {

int sync_lost_count; bool frame_intact; + + dma_addr_t palette_dma_handle; + void *palette_base; + struct completion palette_loaded; }; #define to_tilcdc_crtc(x) container_of(x, struct tilcdc_crtc, base)

@@ -100,6 +108,55 @@ static void set_scanout(struct drm_crtc *crtc, struct drm_framebuffer *fb) tilcdc_crtc->curr_fb = fb; }

+/* + * The driver currently only supports the RGB565 format for revision 1. For + * 16 bits-per-pixel the palette block is bypassed, but the first 32 bytes of + * the framebuffer are still considered palette. The first 16-bit entry must + * be 0x4000 while all other entries must be zeroed. + */ +static void tilcdc_crtc_load_palette(struct drm_crtc *crtc) +{ + u32 dma_fb_base, dma_fb_ceiling, raster_ctl; + struct tilcdc_crtc *tilcdc_crtc; + struct drm_device *dev; + u16 *first_entry; + + dev = crtc->dev; + tilcdc_crtc = to_tilcdc_crtc(crtc); + first_entry = tilcdc_crtc->palette_base; + + *first_entry = TILCDC_REV1_PALETTE_FIRST_ENTRY; + + dma_fb_base = tilcdc_read(dev, LCDC_DMA_FB_BASE_ADDR_0_REG); + dma_fb_ceiling = tilcdc_read(dev, LCDC_DMA_FB_CEILING_ADDR_0_REG); + raster_ctl = tilcdc_read(dev, LCDC_RASTER_CTRL_REG); + + /* Tell the LCDC where the palette is located. */ + tilcdc_write(dev, LCDC_DMA_FB_BASE_ADDR_0_REG, + tilcdc_crtc->palette_dma_handle); + tilcdc_write(dev, LCDC_DMA_FB_CEILING_ADDR_0_REG, + (u32)tilcdc_crtc->palette_dma_handle + + TILCDC_REV1_PALETTE_SIZE - 1); + + /* Load it. */ + tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, + LCDC_PALETTE_LOAD_MODE(DATA_ONLY)); + tilcdc_set(dev, LCDC_RASTER_CTRL_REG, + LCDC_PALETTE_LOAD_MODE(PALETTE_ONLY)); + + /* Enable the LCDC and wait for palette to be loaded. */ + tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_V1_PL_INT_ENA); + tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE); + + wait_for_completion(&tilcdc_crtc->palette_loaded); + + /* Restore the registers. */ + tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE); + tilcdc_write(dev, LCDC_DMA_FB_BASE_ADDR_0_REG, dma_fb_base); + tilcdc_write(dev, LCDC_DMA_FB_CEILING_ADDR_0_REG, dma_fb_ceiling); + tilcdc_write(dev, LCDC_RASTER_CTRL_REG, raster_ctl); +} + static void tilcdc_crtc_enable_irqs(struct drm_device *dev) { struct tilcdc_drm_private *priv = dev->dev_private; @@ -154,6 +211,7 @@ static void tilcdc_crtc_enable(struct drm_crtc *crtc) { struct drm_device *dev = crtc->dev; struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc); + struct tilcdc_drm_private *priv = dev->dev_private;

WARN_ON(!drm_modeset_is_locked(&crtc->mutex));

@@ -164,6 +222,9 @@ static void tilcdc_crtc_enable(struct drm_crtc *crtc)

reset(crtc);

+ if (priv->rev == 1 && !completion_done(&tilcdc_crtc->palette_loaded)) + tilcdc_crtc_load_palette(crtc); + tilcdc_crtc_enable_irqs(dev);

tilcdc_clear(dev, LCDC_DMA_CTRL_REG, LCDC_DUAL_FRAME_BUFFER_ENABLE); @@ -804,6 +865,14 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc) dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underfow", __func__, stat);

+ if (priv->rev == 1) { + if (stat & LCDC_PL_LOAD_DONE) { + complete(&tilcdc_crtc->palette_loaded); + tilcdc_clear(dev, + LCDC_RASTER_CTRL_REG, LCDC_V1_PL_INT_ENA); + } + } + /* For revision 2 only */ if (priv->rev == 2) { if (stat & LCDC_FRAME_DONE) { @@ -845,6 +914,16 @@ struct drm_crtc *tilcdc_crtc_create(struct drm_device *dev) return NULL; }

+ if (priv->rev == 1) { + init_completion(&tilcdc_crtc->palette_loaded); + tilcdc_crtc->palette_base = dmam_alloc_coherent(dev->dev, + TILCDC_REV1_PALETTE_SIZE, + &tilcdc_crtc->palette_dma_handle, + GFP_KERNEL | __GFP_ZERO); + if (!tilcdc_crtc->palette_base) + return ERR_PTR(-ENOMEM); + } + crtc = &tilcdc_crtc->base;

ret = tilcdc_plane_init(dev, &tilcdc_crtc->primary);