Not all pixelvalve FIFOs in vc5 have the same depth, so we need to add that to our vc4_crtc_data structure to be able to compute the fill level properly later on.
Signed-off-by: Maxime Ripard maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_crtc.c | 19 ++++++++++++++++--- drivers/gpu/drm/vc4/vc4_drv.h | 3 +++ 2 files changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c index ea55d4ca2766..e9d71153c6c6 100644 --- a/drivers/gpu/drm/vc4/vc4_crtc.c +++ b/drivers/gpu/drm/vc4/vc4_crtc.c @@ -251,10 +251,20 @@ vc4_crtc_update_gamma_lut(struct drm_crtc *crtc) vc4_crtc_lut_load(crtc); }
-static u32 vc4_get_fifo_full_level(u32 format) +static u32 vc4_get_fifo_full_level(struct vc4_crtc *vc4_crtc, u32 format) { - static const u32 fifo_len_bytes = 64; + u32 fifo_len_bytes = vc4_crtc->data->fifo_depth;
+ /* + * Pixels are pulled from the HVS if the number of bytes is + * lower than the FIFO full level. + * + * The latency of the pixel fetch mechanism is 6 pixels, so we + * need to convert those 6 pixels in bytes, depending on the + * format, and then subtract that from the length of the FIFO + * to make sure we never end up in a situation where the FIFO + * is full. + */ switch (format) { case PV_CONTROL_FORMAT_DSIV_16: case PV_CONTROL_FORMAT_DSIC_16: @@ -369,7 +379,7 @@ static void vc4_crtc_config_pv(struct drm_crtc *crtc)
CRTC_WRITE(PV_CONTROL, VC4_SET_FIELD(format, PV_CONTROL_FORMAT) | - VC4_SET_FIELD(vc4_get_fifo_full_level(format), + VC4_SET_FIELD(vc4_get_fifo_full_level(vc4_crtc, format), PV_CONTROL_FIFO_LEVEL) | VC4_SET_FIELD(pixel_rep - 1, PV_CONTROL_PIXEL_REP) | PV_CONTROL_CLR_AT_START | @@ -1068,6 +1078,7 @@ static const struct vc4_crtc_data bcm2835_pv0_data = { .hvs_available_channels = BIT(0), .hvs_output = 0, .debugfs_name = "crtc0_regs", + .fifo_depth = 64, .pixels_per_clock = 1, .encoder_types = { [PV_CONTROL_CLK_SELECT_DSI] = VC4_ENCODER_TYPE_DSI0, @@ -1079,6 +1090,7 @@ static const struct vc4_crtc_data bcm2835_pv1_data = { .hvs_available_channels = BIT(2), .hvs_output = 2, .debugfs_name = "crtc1_regs", + .fifo_depth = 64, .pixels_per_clock = 1, .encoder_types = { [PV_CONTROL_CLK_SELECT_DSI] = VC4_ENCODER_TYPE_DSI1, @@ -1090,6 +1102,7 @@ static const struct vc4_crtc_data bcm2835_pv2_data = { .hvs_available_channels = BIT(1), .hvs_output = 1, .debugfs_name = "crtc2_regs", + .fifo_depth = 64, .pixels_per_clock = 1, .encoder_types = { [PV_CONTROL_CLK_SELECT_DPI_SMI_HDMI] = VC4_ENCODER_TYPE_HDMI, diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h index 6468c6df20b6..1ac27f8ec725 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.h +++ b/drivers/gpu/drm/vc4/vc4_drv.h @@ -450,6 +450,9 @@ to_vc4_encoder(struct drm_encoder *encoder) }
struct vc4_crtc_data { + /* Depth of the PixelValve FIFO in bytes */ + unsigned int fifo_depth; + /* Which channels of the HVS can the output source from */ unsigned int hvs_available_channels;