Hi Nicolas,

Missed some comments in my last mail.

On 8/11/2025 11:25 PM, Nicolas Dufresne wrote:

Le dimanche 10 août 2025 à 21:24 +0000, Jonas Karlman a écrit :

quoted

From: Alex Bee <redacted>

The RK3328 VDEC has a HW quirk that require QoS to be disabled when HEVC
or VP9 is decoded, otherwise the decoded picture may become corrupted.

Add a RK3328 variant with a quirk flag to disable QoS when before
decoding is started.

Signed-off-by: Alex Bee <redacted>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
---
Changes in v2:
- No change
---
 drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c |  9 +++++++++
 drivers/media/platform/rockchip/rkvdec/rkvdec-regs.h |  2 ++
 drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c  | 10 ++++++++++
 drivers/media/platform/rockchip/rkvdec/rkvdec.c      | 12 ++++++++++++
 drivers/media/platform/rockchip/rkvdec/rkvdec.h      |  4 ++++
 5 files changed, 37 insertions(+)

diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c

b/drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c
index 1994ea24f0be..f8bb8c4264f7 100644

--- a/drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c
+++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c

@@ -789,6 +789,15 @@ static int rkvdec_hevc_run(struct rkvdec_ctx *ctx)

 	writel(1, rkvdec->regs + RKVDEC_REG_PREF_LUMA_CACHE_COMMAND);
 	writel(1, rkvdec->regs + RKVDEC_REG_PREF_CHR_CACHE_COMMAND);
 
+	if (rkvdec->quirks & RKVDEC_QUIRK_DISABLE_QOS) {
+		u32 reg;
+
+		reg = readl(rkvdec->regs + RKVDEC_REG_QOS_CTRL);
+		reg |= 0xFFFF;
+		reg &= ~BIT(12);

I wonder if there is a better way to express that, if not, a comment for future
readers would be nice. If read it will, we keep the upper 16bit, and replaced
the lower bits with 0xEFFF (all bits set except 12) ? I'd rather not spend time
thinking if I walk by this code again.

Vendor kernel use following comment to describe the purpose of this [1]:

  HW defeat workaround: VP9 and H.265 power save optimization cause
  decoding corruption, disable optimization here.

From the TRM we can see following for rkvdec_swreg99_qos_ctrl:

  27:26 sw_axi_wr_hurry_level
    00: hurry off 
    01~11: hurry level 
  25:24 sw_axi_rd_hurry_level
    00: hurry off 
    01~11: hurry level 
  23:16 sw_bus2mc_buffer_qos_level
    range is: 0~255
    the value is means that left space <=
    sw_bus2mc_buffer_qos_level, it will give hurry
  15:0 swreg_block_gating_e

So yes this set swreg_block_gating_e to 0xEFFF. Possible this configure
hw to not auto gate most internal clocks?

Could add a comment and possible use something like following:

  reg &= GENMASK(31, 16);
  reg |= 0xEFFF;

[1] https://github.com/Kwiboo/linux-rockchip/blob/linux-6.1-stan-rkr6.1/drivers/video/rockchip/mpp/mpp_rkvdec.c#L857-L867

quoted

+		writel(reg, rkvdec->regs + RKVDEC_REG_QOS_CTRL);
+	}
+
 	/* Start decoding! */
 	reg = (run.pps->flags & V4L2_HEVC_PPS_FLAG_TILES_ENABLED) ?
 		0 : RKVDEC_WR_DDR_ALIGN_EN;

diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-regs.h

b/drivers/media/platform/rockchip/rkvdec/rkvdec-regs.h
index 540c8bdf24e4..c627b6b6f53a 100644

--- a/drivers/media/platform/rockchip/rkvdec/rkvdec-regs.h
+++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-regs.h

@@ -219,6 +219,8 @@

 #define RKVDEC_REG_H264_ERR_E				0x134
 #define RKVDEC_H264_ERR_EN_HIGHBITS(x)			((x) & 0x3fffffff)
 
+#define RKVDEC_REG_QOS_CTRL				0x18C
+
 #define RKVDEC_REG_PREF_LUMA_CACHE_COMMAND		0x410
 #define RKVDEC_REG_PREF_CHR_CACHE_COMMAND		0x450
 

diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c

b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
index 0e7e16f20eeb..cadb9d592308 100644

--- a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
+++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c

@@ -824,6 +824,16 @@ static int rkvdec_vp9_run(struct rkvdec_ctx *ctx)

 	writel(1, rkvdec->regs + RKVDEC_REG_PREF_CHR_CACHE_COMMAND);
 
 	writel(0xe, rkvdec->regs + RKVDEC_REG_STRMD_ERR_EN);
+
+	if (rkvdec->quirks & RKVDEC_QUIRK_DISABLE_QOS) {
+		u32 reg;
+
+		reg = readl(rkvdec->regs + RKVDEC_REG_QOS_CTRL);
+		reg |= 0xFFFF;
+		reg &= ~BIT(12);
+		writel(reg, rkvdec->regs + RKVDEC_REG_QOS_CTRL);

Can we deduplicate that ?

Guess so, any suggestion on how to best do that?

One possible way that comes to mind:

  if (rkvdec->quirks & RKVDEC_QUIRK_DISABLE_QOS)
	rkvdec_quirk_disable_qos(rkvdec);

quoted

+	}
+
 	/* Start decoding! */
 	writel(RKVDEC_INTERRUPT_DEC_E | RKVDEC_CONFIG_DEC_CLK_GATE_E |
 	       RKVDEC_TIMEOUT_E | RKVDEC_BUF_EMPTY_E,

[snip]