From 93396d0f9c027654eb09151d2e22fe78a39feedb Mon Sep 17 00:00:00 2001 From: Sean Paul Date: Wed, 19 Nov 2014 13:04:49 -0500 Subject: [PATCH] drm/tegra: dc: Select root window for event dispatch In finish pageflip, the driver was not selecting the root window when dispatching events. This exposed a race where a plane update would change the window selection and cause tegra_dc_finish_page_flip to check the wrong base address. This patch also protects access to the window selection register as well as the registers affected by it. Signed-off-by: Sean Paul Signed-off-by: Thierry Reding --- drivers/gpu/drm/tegra/dc.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c index ef36f9d5e35e..978993fa3a36 100644 --- a/drivers/gpu/drm/tegra/dc.c +++ b/drivers/gpu/drm/tegra/dc.c @@ -168,7 +168,7 @@ static int tegra_dc_setup_window(struct tegra_dc *dc, unsigned int index, const struct tegra_dc_window *window) { unsigned h_offset, v_offset, h_size, v_size, h_dda, v_dda, bpp; - unsigned long value; + unsigned long value, flags; bool yuv, planar; /* @@ -181,6 +181,8 @@ static int tegra_dc_setup_window(struct tegra_dc *dc, unsigned int index, else bpp = planar ? 1 : 2; + spin_lock_irqsave(&dc->lock, flags); + value = WINDOW_A_SELECT << index; tegra_dc_writel(dc, value, DC_CMD_DISPLAY_WINDOW_HEADER); @@ -273,6 +275,7 @@ static int tegra_dc_setup_window(struct tegra_dc *dc, unsigned int index, case TEGRA_BO_TILING_MODE_BLOCK: DRM_ERROR("hardware doesn't support block linear mode\n"); + spin_unlock_irqrestore(&dc->lock, flags); return -EINVAL; } @@ -331,6 +334,8 @@ static int tegra_dc_setup_window(struct tegra_dc *dc, unsigned int index, tegra_dc_window_commit(dc, index); + spin_unlock_irqrestore(&dc->lock, flags); + return 0; } @@ -338,11 +343,14 @@ static int tegra_window_plane_disable(struct drm_plane *plane) { struct tegra_dc *dc = to_tegra_dc(plane->crtc); struct tegra_plane *p = to_tegra_plane(plane); + unsigned long flags; u32 value; if (!plane->crtc) return 0; + spin_lock_irqsave(&dc->lock, flags); + value = WINDOW_A_SELECT << p->index; tegra_dc_writel(dc, value, DC_CMD_DISPLAY_WINDOW_HEADER); @@ -352,6 +360,8 @@ static int tegra_window_plane_disable(struct drm_plane *plane) tegra_dc_window_commit(dc, p->index); + spin_unlock_irqrestore(&dc->lock, flags); + return 0; } @@ -699,14 +709,16 @@ static int tegra_dc_set_base(struct tegra_dc *dc, int x, int y, struct tegra_bo *bo = tegra_fb_get_plane(fb, 0); unsigned int h_offset = 0, v_offset = 0; struct tegra_bo_tiling tiling; + unsigned long value, flags; unsigned int format, swap; - unsigned long value; int err; err = tegra_fb_get_tiling(fb, &tiling); if (err < 0) return err; + spin_lock_irqsave(&dc->lock, flags); + tegra_dc_writel(dc, WINDOW_A_SELECT, DC_CMD_DISPLAY_WINDOW_HEADER); value = fb->offsets[0] + y * fb->pitches[0] + @@ -752,6 +764,7 @@ static int tegra_dc_set_base(struct tegra_dc *dc, int x, int y, case TEGRA_BO_TILING_MODE_BLOCK: DRM_ERROR("hardware doesn't support block linear mode\n"); + spin_unlock_irqrestore(&dc->lock, flags); return -EINVAL; } @@ -778,6 +791,8 @@ static int tegra_dc_set_base(struct tegra_dc *dc, int x, int y, tegra_dc_writel(dc, value << 8, DC_CMD_STATE_CONTROL); tegra_dc_writel(dc, value, DC_CMD_STATE_CONTROL); + spin_unlock_irqrestore(&dc->lock, flags); + return 0; } @@ -823,11 +838,16 @@ static void tegra_dc_finish_page_flip(struct tegra_dc *dc) bo = tegra_fb_get_plane(crtc->primary->fb, 0); + spin_lock_irqsave(&dc->lock, flags); + /* check if new start address has been latched */ + tegra_dc_writel(dc, WINDOW_A_SELECT, DC_CMD_DISPLAY_WINDOW_HEADER); tegra_dc_writel(dc, READ_MUX, DC_CMD_STATE_ACCESS); base = tegra_dc_readl(dc, DC_WINBUF_START_ADDR); tegra_dc_writel(dc, 0, DC_CMD_STATE_ACCESS); + spin_unlock_irqrestore(&dc->lock, flags); + if (base == bo->paddr + crtc->primary->fb->offsets[0]) { drm_crtc_send_vblank_event(crtc, dc->event); drm_crtc_vblank_put(crtc); -- GitLab