Changelog v2: Added details of original patch in chromium kernel

Changelog v1: When fimd is turned off, we disable the clocks which will stop the dma. Now if we remove the current framebuffer, we cannot disable the overlay but the current framebuffer will still be freed. When fimd resumes, the dma will continue from where it left off and will throw a PAGE FAULT since the memory was freed.

This patch fixes the above problem by disabling the fimd windows before disabling the fimd clocks. It also keeps track of which windows were currently active by setting the 'resume' flag. When fimd resumes, the window with a resume flag set is enabled again.

Now if a current fb is removed when fimd is off, fimd_win_disable will set the 'resume' flag of that window to zero and return. So when fimd resumes, that window will not be resumed.

This patch is based on the following two patches: http://git.chromium.org/gitweb/?p=chromiumos/third_party/kernel.git;a=commit... http://git.chromium.org/gitweb/?p=chromiumos/third_party/kernel.git;a=commit... These two patches are rebased onto the current kernel with additional changes like removing 'fimd_win_commit' call from the resume function since this is taken care by encoder dpms, and the modification of resume flag in win_disable.

Signed-off-by: Prathyush K prathyush.k@samsung.com Signed-off-by: Sean Paul seanpaul@chromium.org Signed-off-by: Stephane Marchesin marcheu@chromium.org Signed-off-by: Inki Dae inki.dae@samsung.com --- drivers/gpu/drm/exynos/exynos_drm_fimd.c | 40 +++++++++++++++++++++++++++++- 1 files changed, 39 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c index 9b5c77d..5067ece 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c @@ -83,6 +83,7 @@ struct fimd_win_data { unsigned int buf_offsize; unsigned int line_size; /* bytes */ bool enabled; + bool resume; };

struct fimd_context { @@ -602,6 +603,12 @@ static void fimd_win_disable(struct device *dev, int zpos)

win_data = &ctx->win_data[win];

+ if (ctx->suspended) { + /* do not resume this window*/ + win_data->resume = false; + return; + } + /* protect windows */ val = readl(ctx->regs + SHADOWCON); val |= SHADOWCON_WINx_PROTECT(win); @@ -815,11 +822,38 @@ static int fimd_clock(struct fimd_context *ctx, bool enable) return 0; }

+static void fimd_window_suspend(struct device *dev) +{ + struct fimd_context *ctx = get_fimd_context(dev); + struct fimd_win_data *win_data; + int i; + + for (i = 0; i < WINDOWS_NR; i++) { + win_data = &ctx->win_data[i]; + win_data->resume = win_data->enabled; + fimd_win_disable(dev, i); + } + fimd_wait_for_vblank(dev); +} + +static void fimd_window_resume(struct device *dev) +{ + struct fimd_context *ctx = get_fimd_context(dev); + struct fimd_win_data *win_data; + int i; + + for (i = 0; i < WINDOWS_NR; i++) { + win_data = &ctx->win_data[i]; + win_data->enabled = win_data->resume; + win_data->resume = false; + } +} + static int fimd_activate(struct fimd_context *ctx, bool enable) { + struct device *dev = ctx->subdrv.dev; if (enable) { int ret; - struct device *dev = ctx->subdrv.dev;

ret = fimd_clock(ctx, true); if (ret < 0) @@ -830,7 +864,11 @@ static int fimd_activate(struct fimd_context *ctx, bool enable) /* if vblank was enabled status, enable it again. */ if (test_and_clear_bit(0, &ctx->irq_flags)) fimd_enable_vblank(dev); + + fimd_window_resume(dev); } else { + fimd_window_suspend(dev); + fimd_clock(ctx, false); ctx->suspended = true; }