On Tue, 22 Aug 2023, Suraj Kandpal <suraj.kandpal@xxxxxxxxx> wrote:
> Add function to read any PPS register based on the
> intel_dsc_pps enum provided. Add a function which will call the
> new pps read function and place it in crtc state. Only PPS0 and
> PPS1 are readout the rest of the registers will be read in upcoming
> patches.
>
> --v2
> -Changes in read function as PPS enum is removed
> -Initialize pps_val as 0 in pps_read func itself [Jani]
> -Create a function that gets the required register and call that
> in the common read function [Jani]
> -Move the drm_WARN_ON one abstraction layer above [Jani]
>
> --v3
> -Send both reg values regardless of dsc engine no [Jani]
> -Don't use num_vdsc_instances stick to dsc_split field [Ankit]
>
> --v4
> -Manipulate the reg values instead of creating MACRO to change
> name of pps [Ankit]
>
> --v5
> -Read dsc reg values using array rather than individual variables
> [Ankit]
> -Loop the verification of all dsc engine reads to future proof it
> [Ankit]
> -Keep the fix me comment in this patch and remove it in later one
> where we add other readouts [Ankit]
> -Add switch statement that fills in the required registers based on
> no of vdsc engines per pipe.
>
> --v7
> -Pass no of vdsc instances from read_reg function [Ankit]
> -Fix issue where arrays do not get freed on return for read_and_verify
> func [Ankit]
>
> --v8
> -Simplify reading and verifying of register and remove dynamically
> allocated arrays [Jani]
> -Remove no_ from no_vdsc_per_pipe and wherever else it applies [Ankit]
>
> --v9
> -change variable name to dsc_reg_size rather than vdsc_per_pipe [Ankit]
>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_vdsc.c | 118 ++++++++++++------
> .../gpu/drm/i915/display/intel_vdsc_regs.h | 12 ++
> 2 files changed, 94 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index fbe8ce9fe1ab..d505fa971dff 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -371,6 +371,28 @@ int intel_dsc_get_num_vdsc_instances(const struct intel_crtc_state *crtc_state)
> return num_vdsc_instances;
> }
>
> +static void intel_dsc_get_pps_reg(const struct intel_crtc_state *crtc_state, int pps,
> + i915_reg_t *dsc_reg, int dsc_reg_size)
> +{
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> + enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
> + enum pipe pipe = crtc->pipe;
> + bool pipe_dsc;
> +
> + pipe_dsc = is_pipe_dsc(crtc, cpu_transcoder);
> +
> + switch (dsc_reg_size) {
dsc_reg_size is the size of the dsc_reg array, nothing more, nothing
else. You just have to ensure you don't overflow it.
It'll always be 2 here.
This function should get as many registers as indicated by
intel_dsc_get_vdsc_per_pipe(crtc_state), but limited by dsc_reg_size.
> + case 2:
> + dsc_reg[1] = pipe_dsc ? ICL_DSC1_PPS_REG(pipe, pps) : DSCC_PPS_REG(pps);
> + fallthrough;
> + case 1:
> + dsc_reg[0] = pipe_dsc ? ICL_DSC0_PPS_REG(pipe, pps) : DSCA_PPS_REG(pps);
> + break;
> + default:
> + MISSING_CASE(dsc_reg_size);
> + }
> +}
> +
> static void intel_dsc_pps_configure(const struct intel_crtc_state *crtc_state)
> {
> struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> @@ -1000,17 +1022,72 @@ void intel_dsc_disable(const struct intel_crtc_state *old_crtc_state)
> }
> }
>
> +static bool intel_dsc_read_pps_reg(struct intel_crtc_state *crtc_state,
> + int pps, u32 *pps_val)
> +{
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> + struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> + const int vdsc_per_pipe = intel_dsc_get_vdsc_per_pipe(crtc_state);
> + i915_reg_t dsc_reg[2];
> + int i;
> +
> + *pps_val = 0;
> + drm_WARN_ON_ONCE(&i915->drm, ARRAY_SIZE(dsc_reg) < vdsc_per_pipe);
> +
> + intel_dsc_get_pps_reg(crtc_state, pps, dsc_reg, ARRAY_SIZE(dsc_reg));
> +
> + for (i = 0; i < min_t(int, ARRAY_SIZE(dsc_reg), vdsc_per_pipe); i++) {
> + u32 pps_temp;
> +
> + pps_temp = intel_de_read(i915, dsc_reg[i]);
> +
> + if (i == 0)
> + *pps_val = intel_de_read(i915, dsc_reg[i]);
I actually took the trouble of re-writing this for loop for you [1]. Why
would you change it to duplicate the read here? I just don't understand.
[1] https://lore.kernel.org/r/87jztv9tri.fsf@xxxxxxxxx
> + else if (pps_temp != *pps_val)
> + return false;
> + }
> +
> + return true;
> +}
> +
> +static void intel_dsc_read_and_verify_pps_reg(struct intel_crtc_state *crtc_state,
> + int pps, u32 *pps_val)
> +{
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> + struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> + int ret;
> +
> + ret = intel_dsc_read_pps_reg(crtc_state, pps, pps_val);
> + drm_WARN_ON(&i915->drm, !ret);
> +}
> +
> +static void intel_dsc_get_pps_config(struct intel_crtc_state *crtc_state)
> +{
> + struct drm_dsc_config *vdsc_cfg = &crtc_state->dsc.config;
> + u32 pps_temp1, pps_temp2;
> +
> + /* FIXME: add more state readout as needed */
> +
> + /* Readout PPS_0 and PPS_1 registers */
> + intel_dsc_read_and_verify_pps_reg(crtc_state, 0, &pps_temp1);
> + intel_dsc_read_and_verify_pps_reg(crtc_state, 1, &pps_temp2);
> +
> + vdsc_cfg->bits_per_pixel = pps_temp2;
> +
> + if (pps_temp1 & DSC_NATIVE_420_ENABLE)
> + vdsc_cfg->bits_per_pixel >>= 1;
> +
> + crtc_state->dsc.compressed_bpp = vdsc_cfg->bits_per_pixel >> 4;
> +}
> +
> void intel_dsc_get_config(struct intel_crtc_state *crtc_state)
> {
> struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> - struct drm_dsc_config *vdsc_cfg = &crtc_state->dsc.config;
> enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
> - enum pipe pipe = crtc->pipe;
> enum intel_display_power_domain power_domain;
> intel_wakeref_t wakeref;
> - u32 dss_ctl1, dss_ctl2, pps0 = 0, pps1 = 0, pps_temp0, pps_temp1;
> - int vdsc_instances_per_pipe;
> + u32 dss_ctl1, dss_ctl2;
>
> if (!intel_dsc_source_support(crtc_state))
> return;
> @@ -1031,38 +1108,7 @@ void intel_dsc_get_config(struct intel_crtc_state *crtc_state)
> crtc_state->dsc.dsc_split = (dss_ctl2 & RIGHT_BRANCH_VDSC_ENABLE) &&
> (dss_ctl1 & JOINER_ENABLE);
>
> - /* FIXME: add more state readout as needed */
> -
> - vdsc_instances_per_pipe = intel_dsc_get_vdsc_per_pipe(crtc_state);
> -
> - /* PPS0 & PPS1 */
> - if (!is_pipe_dsc(crtc, cpu_transcoder)) {
> - pps1 = intel_de_read(dev_priv, DSCA_PICTURE_PARAMETER_SET_1);
> - if (vdsc_instances_per_pipe > 1) {
> - pps_temp1 = intel_de_read(dev_priv, DSCC_PICTURE_PARAMETER_SET_1);
> - drm_WARN_ON(&dev_priv->drm, pps1 != pps_temp1);
> - }
> - } else {
> - pps0 = intel_de_read(dev_priv,
> - ICL_DSC0_PICTURE_PARAMETER_SET_0(pipe));
> - pps1 = intel_de_read(dev_priv,
> - ICL_DSC0_PICTURE_PARAMETER_SET_1(pipe));
> - if (vdsc_instances_per_pipe > 1) {
> - pps_temp0 = intel_de_read(dev_priv,
> - ICL_DSC1_PICTURE_PARAMETER_SET_0(pipe));
> - pps_temp1 = intel_de_read(dev_priv,
> - ICL_DSC1_PICTURE_PARAMETER_SET_1(pipe));
> - drm_WARN_ON(&dev_priv->drm, pps0 != pps_temp0);
> - drm_WARN_ON(&dev_priv->drm, pps1 != pps_temp1);
> - }
> - }
> -
> - vdsc_cfg->bits_per_pixel = pps1;
> -
> - if (pps0 & DSC_NATIVE_420_ENABLE)
> - vdsc_cfg->bits_per_pixel >>= 1;
> -
> - crtc_state->dsc.compressed_bpp = vdsc_cfg->bits_per_pixel >> 4;
> + intel_dsc_get_pps_config(crtc_state);
> out:
> intel_display_power_put(dev_priv, power_domain, wakeref);
> }
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> index 785ede31116e..862dc708c5fc 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc_regs.h
> @@ -78,6 +78,10 @@
> /* Icelake Display Stream Compression Registers */
> #define DSCA_PICTURE_PARAMETER_SET_0 _MMIO(0x6B200)
> #define DSCC_PICTURE_PARAMETER_SET_0 _MMIO(0x6BA00)
> +#define DSCA_PPS_0 0x6B200
> +#define DSCC_PPS_0 0x6BA00
These aren't, and should not be, used directly, so please prefix them
with _ i.e. DSCA_PPS_0.
> +#define DSCA_PPS_REG(pps) _MMIO(DSCA_PPS_0 + (pps) * 4)
> +#define DSCC_PPS_REG(pps) _MMIO(DSCC_PPS_0 + (pps) * 4)
Register macros should never have _REG suffix.
> #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PB 0x78270
> #define _ICL_DSC1_PICTURE_PARAMETER_SET_0_PB 0x78370
> #define _ICL_DSC0_PICTURE_PARAMETER_SET_0_PC 0x78470
> @@ -88,6 +92,14 @@
> #define ICL_DSC1_PICTURE_PARAMETER_SET_0(pipe) _MMIO_PIPE((pipe) - PIPE_B, \
> _ICL_DSC1_PICTURE_PARAMETER_SET_0_PB, \
> _ICL_DSC1_PICTURE_PARAMETER_SET_0_PC)
> +#define ICL_DSC0_PPS_0(pipe) _PICK_EVEN((pipe) - PIPE_B, \
> + _ICL_DSC0_PICTURE_PARAMETER_SET_0_PB, \
> + _ICL_DSC0_PICTURE_PARAMETER_SET_0_PC)
> +#define ICL_DSC1_PPS_0(pipe) _PICK_EVEN((pipe) - PIPE_B, \
> + _ICL_DSC1_PICTURE_PARAMETER_SET_0_PB, \
> + _ICL_DSC1_PICTURE_PARAMETER_SET_0_PC)
Ditto about _ prefix.
> +#define ICL_DSC0_PPS_REG(pipe, pps) _MMIO(ICL_DSC0_PPS_0(pipe) + ((pps) * 4))
> +#define ICL_DSC1_PPS_REG(pipe, pps) _MMIO(ICL_DSC1_PPS_0(pipe) + ((pps) * 4))
Ditto about _REG suffix.
> #define DSC_NATIVE_422_ENABLE BIT(23)
> #define DSC_NATIVE_420_ENABLE BIT(22)
> #define DSC_ALT_ICH_SEL (1 << 20)
--
Jani Nikula, Intel Open Source Graphics Center
