[PATCH v3 3/4] drm/bridge: analogix_dp: add the PSR function support

Sean Paul seanpaul at chromium.org
Fri Jul 1 19:46:09 UTC 2016


On Fri, Jul 1, 2016 at 5:19 AM, Yakir Yang <ykk at rock-chips.com> wrote:
> The full name of PSR is Panel Self Refresh, panel device could refresh
> itself with the hardware framebuffer in panel, this would make lots of
> sense to save the power consumption.
>
> This patch have exported two symbols for platform driver to implement
> the PSR function in hardware side:
> - analogix_dp_active_psr()
> - analogix_dp_inactive_psr()
>
> Signed-off-by: Yakir Yang <ykk at rock-chips.com>
> ---
> Changes in v3:
> - split analogix_dp_enable_psr(), make it more clearly
>     analogix_dp_detect_sink_psr()
>     analogix_dp_enable_sink_psr()
> - remove some nosie register setting comments
>
> Changes in v2:
> - introduce in v2, splite the common Analogix DP changes out
>
>  drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 64 ++++++++++++++++++++++
>  drivers/gpu/drm/bridge/analogix/analogix_dp_core.h |  4 ++
>  drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c  | 54 ++++++++++++++++++
>  drivers/gpu/drm/bridge/analogix/analogix_dp_reg.h  | 28 ++++++++++
>  include/drm/bridge/analogix_dp.h                   |  3 +
>  5 files changed, 153 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 32715da..b557097 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -97,6 +97,66 @@ static int analogix_dp_detect_hpd(struct analogix_dp_device *dp)
>         return 0;
>  }
>
> +int analogix_dp_active_psr(struct device *dev)
> +{
> +       struct analogix_dp_device *dp = dev_get_drvdata(dev);
> +
> +       if (!dp->psr_support)
> +               return -EINVAL;
> +
> +       analogix_dp_send_psr_spd(dp, EDP_VSC_PSR_STATE_ACTIVE |
> +                                EDP_VSC_PSR_CRC_VALUES_VALID);
> +       return 0;
> +}
> +EXPORT_SYMBOL_GPL(analogix_dp_active_psr);
> +
> +int analogix_dp_inactive_psr(struct device *dev)
> +{
> +       struct analogix_dp_device *dp = dev_get_drvdata(dev);
> +
> +       if (!dp->psr_support)
> +               return -EINVAL;
> +
> +       analogix_dp_send_psr_spd(dp, 0);
> +       return 0;
> +}
> +EXPORT_SYMBOL_GPL(analogix_dp_inactive_psr);
> +
> +static bool analogix_dp_detect_sink_psr(struct analogix_dp_device *dp)
> +{
> +       unsigned char psr_version;
> +
> +       analogix_dp_read_byte_from_dpcd(dp, DP_PSR_SUPPORT, &psr_version);
> +       dev_info(dp->dev, "Panel PSR version : %x\n", psr_version);
> +

This info message is likely to be spammy since it's printed everytime
the panel toggle on. Perhaps downgrade to debug level.

> +       return (psr_version & DP_PSR_IS_SUPPORTED) ? true : false;
> +}
> +
> +static int analogix_dp_enable_sink_psr(struct analogix_dp_device *dp)

Return type is int, but the function never fails and you don't check
the return value when calling it. Seems like this should be void.

> +{
> +       unsigned char psr_en;
> +
> +       /* Disable psr function */
> +       analogix_dp_read_byte_from_dpcd(dp, DP_PSR_EN_CFG, &psr_en);
> +       psr_en &= ~DP_PSR_ENABLE;
> +       analogix_dp_write_byte_to_dpcd(dp, DP_PSR_EN_CFG, psr_en);
> +
> +       /* Main-Link transmitter remains active during PSR active states */
> +       analogix_dp_read_byte_from_dpcd(dp, DP_PSR_EN_CFG, &psr_en);
> +       psr_en = DP_PSR_MAIN_LINK_ACTIVE | DP_PSR_CRC_VERIFICATION;

Why read psr_en if you're just going to overwrite it? Perhaps you meant |= here.

> +       analogix_dp_write_byte_to_dpcd(dp, DP_PSR_EN_CFG, psr_en);
> +
> +       /* Enable psr function */
> +       analogix_dp_read_byte_from_dpcd(dp, DP_PSR_EN_CFG, &psr_en);
> +       psr_en = DP_PSR_ENABLE | DP_PSR_MAIN_LINK_ACTIVE |
> +                DP_PSR_CRC_VERIFICATION;

Again, no need to read if you're just overwriting.

> +       analogix_dp_write_byte_to_dpcd(dp, DP_PSR_EN_CFG, psr_en);
> +
> +       analogix_dp_enable_psr_crc(dp);
> +
> +       return 0;
> +}
> +
>  static unsigned char analogix_dp_calc_edid_check_sum(unsigned char *edid_data)
>  {
>         int i;
> @@ -921,6 +981,10 @@ static void analogix_dp_commit(struct analogix_dp_device *dp)
>
>         /* Enable video */
>         analogix_dp_start_video(dp);
> +
> +       dp->psr_support = analogix_dp_detect_sink_psr(dp);
> +       if (dp->psr_support)
> +               analogix_dp_enable_sink_psr(dp);
>  }
>
>  int analogix_dp_get_modes(struct drm_connector *connector)
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> index b456380..6ca5dde 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> @@ -177,6 +177,7 @@ struct analogix_dp_device {
>         int                     hpd_gpio;
>         bool                    force_hpd;
>         unsigned char           edid[EDID_BLOCK_LENGTH * 2];
> +       bool                    psr_support;
>
>         struct analogix_dp_plat_data *plat_data;
>  };
> @@ -278,4 +279,7 @@ int analogix_dp_is_video_stream_on(struct analogix_dp_device *dp);
>  void analogix_dp_config_video_slave_mode(struct analogix_dp_device *dp);
>  void analogix_dp_enable_scrambling(struct analogix_dp_device *dp);
>  void analogix_dp_disable_scrambling(struct analogix_dp_device *dp);
> +void analogix_dp_enable_psr_crc(struct analogix_dp_device *dp);
> +void analogix_dp_send_psr_spd(struct analogix_dp_device *dp, int db1);
> +
>  #endif /* _ANALOGIX_DP_CORE_H */
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> index 48030f0..e8372c7 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> @@ -1322,3 +1322,57 @@ void analogix_dp_disable_scrambling(struct analogix_dp_device *dp)
>         reg |= SCRAMBLING_DISABLE;
>         writel(reg, dp->reg_base + ANALOGIX_DP_TRAINING_PTN_SET);
>  }
> +
> +void analogix_dp_enable_psr_crc(struct analogix_dp_device *dp)
> +{
> +       writel(PSR_VID_CRC_FLUSH | PSR_VID_CRC_ENABLE,
> +              dp->reg_base + ANALOGIX_DP_CRC_CON);
> +
> +       usleep_range(10, 20);

Is this sleep arbitrary, or documented somewhere? Could you add a
comment explaining how this was arrived at?

> +
> +       writel(PSR_VID_CRC_ENABLE, dp->reg_base + ANALOGIX_DP_CRC_CON);
> +}
> +
> +void analogix_dp_send_psr_spd(struct analogix_dp_device *dp, int db1)
> +{
> +       unsigned int val;
> +
> +       /* don't send info frame */
> +       val = readl(dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
> +       val &= ~IF_EN;
> +       writel(val, dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
> +
> +       /* configure single frame update mode */
> +       writel(0x3, dp->reg_base + ANALOGIX_DP_PSR_FRAME_UPDATE_CTRL);
> +
> +       /* configure VSC HB0 ~ HB3 */
> +       writel(0x00, dp->reg_base + ANALOGIX_DP_SPD_HB0);
> +       writel(0x07, dp->reg_base + ANALOGIX_DP_SPD_HB1);
> +       writel(0x02, dp->reg_base + ANALOGIX_DP_SPD_HB2);
> +       writel(0x08, dp->reg_base + ANALOGIX_DP_SPD_HB3);
> +
> +       /* configure VSC HB0 ~ HB3 */
> +       writel(0x00, dp->reg_base + ANALOGIX_DP_SPD_PB0);
> +       writel(0x16, dp->reg_base + ANALOGIX_DP_SPD_PB1);
> +       writel(0xCE, dp->reg_base + ANALOGIX_DP_SPD_PB2);
> +       writel(0x5D, dp->reg_base + ANALOGIX_DP_SPD_PB3);
> +
> +       /* configure DB0 / DB1 values */
> +       writel(0x00, dp->reg_base + ANALOGIX_DP_VSC_SHADOW_DB0);

Lots of hardcoded values here. I think this could be cleaned up.

> +       writel(db1, dp->reg_base + ANALOGIX_DP_VSC_SHADOW_DB1);
> +
> +       /* set reuse spd inforframe */
> +       val = readl(dp->reg_base + ANALOGIX_DP_VIDEO_CTL_3);
> +       val |= REUSE_SPD_EN;
> +       writel(val, dp->reg_base + ANALOGIX_DP_VIDEO_CTL_3);
> +
> +       /* mark info frame update */
> +       val = readl(dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
> +       val = (val | IF_UP) & ~IF_EN;
> +       writel(val, dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
> +
> +       /* send info frame */
> +       val = readl(dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
> +       val |= IF_EN;
> +       writel(val, dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
> +}
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.h
> index cdcc6c5..a2698e4 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.h
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.h
> @@ -22,6 +22,8 @@
>  #define ANALOGIX_DP_VIDEO_CTL_8                        0x3C
>  #define ANALOGIX_DP_VIDEO_CTL_10               0x44
>
> +#define ANALOGIX_DP_SPDIF_AUDIO_CTL_0          0xD8
> +
>  #define ANALOGIX_DP_PLL_REG_1                  0xfc
>  #define ANALOGIX_DP_PLL_REG_2                  0x9e4
>  #define ANALOGIX_DP_PLL_REG_3                  0x9e8
> @@ -30,6 +32,21 @@
>
>  #define ANALOGIX_DP_PD                         0x12c
>
> +#define ANALOGIX_DP_IF_TYPE                    0x244
> +#define ANALOGIX_DP_IF_PKT_DB1                 0x254
> +#define ANALOGIX_DP_IF_PKT_DB2                 0x258
> +#define ANALOGIX_DP_SPD_HB0                    0x2F8
> +#define ANALOGIX_DP_SPD_HB1                    0x2FC
> +#define ANALOGIX_DP_SPD_HB2                    0x300
> +#define ANALOGIX_DP_SPD_HB3                    0x304
> +#define ANALOGIX_DP_SPD_PB0                    0x308
> +#define ANALOGIX_DP_SPD_PB1                    0x30C
> +#define ANALOGIX_DP_SPD_PB2                    0x310
> +#define ANALOGIX_DP_SPD_PB3                    0x314
> +#define ANALOGIX_DP_PSR_FRAME_UPDATE_CTRL      0x318
> +#define ANALOGIX_DP_VSC_SHADOW_DB0             0x31C
> +#define ANALOGIX_DP_VSC_SHADOW_DB1             0x320
> +
>  #define ANALOGIX_DP_LANE_MAP                   0x35C
>
>  #define ANALOGIX_DP_ANALOG_CTL_1               0x370
> @@ -103,6 +120,8 @@
>
>  #define ANALOGIX_DP_SOC_GENERAL_CTL            0x800
>
> +#define ANALOGIX_DP_CRC_CON                    0x890
> +
>  /* ANALOGIX_DP_TX_SW_RESET */
>  #define RESET_DP_TX                            (0x1 << 0)
>
> @@ -151,6 +170,7 @@
>  #define VID_CHK_UPDATE_TYPE_SHIFT              (4)
>  #define VID_CHK_UPDATE_TYPE_1                  (0x1 << 4)
>  #define VID_CHK_UPDATE_TYPE_0                  (0x0 << 4)
> +#define REUSE_SPD_EN                           (0x1 << 3)
>
>  /* ANALOGIX_DP_VIDEO_CTL_8 */
>  #define VID_HRES_TH(x)                         (((x) & 0xf) << 4)
> @@ -376,4 +396,12 @@
>  #define VIDEO_MODE_SLAVE_MODE                  (0x1 << 0)
>  #define VIDEO_MODE_MASTER_MODE                 (0x0 << 0)
>
> +/* ANALOGIX_DP_PKT_SEND_CTL */
> +#define IF_UP                                  (0x1 << 4)
> +#define IF_EN                                  (0x1 << 0)
> +
> +/* ANALOGIX_DP_CRC_CON */
> +#define PSR_VID_CRC_FLUSH                      (0x1 << 2)
> +#define PSR_VID_CRC_ENABLE                     (0x1 << 0)
> +
>  #endif /* _ANALOGIX_DP_REG_H */
> diff --git a/include/drm/bridge/analogix_dp.h b/include/drm/bridge/analogix_dp.h
> index 261b86d..183a336 100644
> --- a/include/drm/bridge/analogix_dp.h
> +++ b/include/drm/bridge/analogix_dp.h
> @@ -38,6 +38,9 @@ struct analogix_dp_plat_data {
>                          struct drm_connector *);
>  };
>
> +int analogix_dp_active_psr(struct device *dev);
> +int analogix_dp_inactive_psr(struct device *dev);

Why active/inactive instead of enable/disable, which is used everywhere else?

> +
>  int analogix_dp_resume(struct device *dev);
>  int analogix_dp_suspend(struct device *dev);
>
> --
> 1.9.1
>
>


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