Re: [PATCH v2 1/7] drm/msm/dpu: add support for DSC encoder v1.2 engine

From: Abhinav Kumar
Date: Fri Apr 28 2023 - 21:10:45 EST




On 4/28/2023 5:30 PM, Dmitry Baryshkov wrote:
On 29/04/2023 02:45, Kuogee Hsieh wrote:
Add support for DSC 1.2 by providing the necessary hooks to program
the DPU DSC 1.2 encoder.

Reported-by: kernel test robot <lkp@xxxxxxxxx>

What exactly was reported?

https://patchwork.freedesktop.org/patch/533188/?series=116789&rev=1#comment_967016

I think we should update the commit text with the change log to mention what was fixed and how.


Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
---
  drivers/gpu/drm/msm/Makefile                   |   1 +
  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h |  34 ++-
  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h     |  14 +-
  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc_1_2.c | 335 +++++++++++++++++++++++++
  drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c         |   7 +-
  5 files changed, 387 insertions(+), 4 deletions(-)
  create mode 100644 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc_1_2.c

diff --git a/drivers/gpu/drm/msm/Makefile b/drivers/gpu/drm/msm/Makefile
index b814fc8..b9af5e4 100644
--- a/drivers/gpu/drm/msm/Makefile
+++ b/drivers/gpu/drm/msm/Makefile
@@ -65,6 +65,7 @@ msm-$(CONFIG_DRM_MSM_DPU) += \
      disp/dpu1/dpu_hw_catalog.o \
      disp/dpu1/dpu_hw_ctl.o \
      disp/dpu1/dpu_hw_dsc.o \
+    disp/dpu1/dpu_hw_dsc_1_2.o \
      disp/dpu1/dpu_hw_interrupts.o \
      disp/dpu1/dpu_hw_intf.o \
      disp/dpu1/dpu_hw_lm.o \
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h
index 71584cd..fc87db1 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h
@@ -1,6 +1,6 @@
  /* SPDX-License-Identifier: GPL-2.0-only */
  /*
- * Copyright (c) 2022. Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2023, Qualcomm Innovation Center, Inc. All rights reserved.
   * Copyright (c) 2015-2018, 2020 The Linux Foundation. All rights reserved.
   */
@@ -241,12 +241,20 @@ enum {
  };
  /**
- * DSC features
+ * DSC sub-blocks/features
   * @DPU_DSC_OUTPUT_CTRL       Configure which PINGPONG block gets
   *                            the pixel output from this DSC.
+ * @DPU_DSC_HW_REV_1_1        DSC block supports dsc 1.1 only
+ * @DPU_DSC_HW_REV_1_2        DSC block supports dsc 1.1 and 1.2
+ * @DPU_DSC_NATIVE_422_EN     Supports native422 and native420 encoding
+ * @DPU_DSC_MAX
   */
  enum {
      DPU_DSC_OUTPUT_CTRL = 0x1,
+    DPU_DSC_HW_REV_1_1,
+    DPU_DSC_HW_REV_1_2,
+    DPU_DSC_NATIVE_422_EN,
+    DPU_DSC_MAX
  };
  /**
@@ -311,6 +319,14 @@ struct dpu_pp_blk {
  };
  /**
+ * struct dpu_dsc_blk - DSC Encoder sub-blk information
+ * @info:   HW register and features supported by this sub-blk
+ */
+struct dpu_dsc_blk {
+    DPU_HW_SUBBLK_INFO;
+};
+
+/**
   * enum dpu_qos_lut_usage - define QoS LUT use cases
   */
  enum dpu_qos_lut_usage {
@@ -459,6 +475,17 @@ struct dpu_pingpong_sub_blks {
  };
  /**
+ * struct dpu_dsc_sub_blks - DSC sub-blks
+ * @enc: DSC encoder sub block
+ * @ctl: DSC controller sub block
+ *
+ */
+struct dpu_dsc_sub_blks {
+    struct dpu_dsc_blk enc;
+    struct dpu_dsc_blk ctl;
+};
+
+/**
   * dpu_clk_ctrl_type - Defines top level clock control signals
   */
  enum dpu_clk_ctrl_type {
@@ -612,10 +639,13 @@ struct dpu_merge_3d_cfg  {
   * struct dpu_dsc_cfg - information of DSC blocks
   * @id                 enum identifying this block
   * @base               register offset of this block
+ * @len:               length of hardware block
   * @features           bit mask identifying sub-blocks/features
+ * @sblk               sub-blocks information
   */
  struct dpu_dsc_cfg {
      DPU_HW_BLK_INFO;
+    const struct dpu_dsc_sub_blks *sblk;
  };
  /**
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h
index 287ec5f..e11240a 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h
@@ -1,5 +1,8 @@
  /* SPDX-License-Identifier: GPL-2.0-only */
-/* Copyright (c) 2020-2022, Linaro Limited */
+/*
+ * Copyright (c) 2020-2022, Linaro Limited
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved
+ */
  #ifndef _DPU_HW_DSC_H
  #define _DPU_HW_DSC_H
@@ -70,6 +73,15 @@ struct dpu_hw_dsc *dpu_hw_dsc_init(const struct dpu_dsc_cfg *cfg,
          void __iomem *addr);
  /**
+ * dpu_hw_dsc_init_1_2 - initializes the v1.2 DSC hw driver block
+ * @cfg:  DSC catalog entry for which driver object is required
+ * @addr: Mapped register io address of MDP
+ * Returns: Error code or allocated dpu_hw_dsc context
+ */
+struct dpu_hw_dsc *dpu_hw_dsc_init_1_2(const struct dpu_dsc_cfg *cfg,
+        void __iomem *addr);
+
+/**
   * dpu_hw_dsc_destroy - destroys dsc driver context
   * @dsc:   Pointer to dsc driver context returned by dpu_hw_dsc_init
   */
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc_1_2.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc_1_2.c
new file mode 100644
index 00000000..a777c7b
--- /dev/null
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc_1_2.c
@@ -0,0 +1,335 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved
+ */
+
+#include <drm/display/drm_dsc_helper.h>
+
+#include "dpu_kms.h"
+#include "dpu_hw_catalog.h"
+#include "dpu_hwio.h"
+#include "dpu_hw_mdss.h"
+#include "dpu_hw_dsc.h"
+
+

Unused empty line

+#define DSC_CMN_MAIN_CNF           0x00
+
+/* DPU_DSC_ENC register offsets */
+#define ENC_DF_CTRL                0x00
+#define ENC_GENERAL_STATUS         0x04
+#define ENC_HSLICE_STATUS          0x08
+#define ENC_OUT_STATUS             0x0C
+#define ENC_INT_STAT               0x10
+#define ENC_INT_CLR                0x14
+#define ENC_INT_MASK               0x18
+#define DSC_MAIN_CONF              0x30
+#define DSC_PICTURE_SIZE           0x34
+#define DSC_SLICE_SIZE             0x38
+#define DSC_MISC_SIZE              0x3C
+#define DSC_HRD_DELAYS             0x40
+#define DSC_RC_SCALE               0x44
+#define DSC_RC_SCALE_INC_DEC       0x48
+#define DSC_RC_OFFSETS_1           0x4C
+#define DSC_RC_OFFSETS_2           0x50
+#define DSC_RC_OFFSETS_3           0x54
+#define DSC_RC_OFFSETS_4           0x58
+#define DSC_FLATNESS_QP            0x5C
+#define DSC_RC_MODEL_SIZE          0x60
+#define DSC_RC_CONFIG              0x64
+#define DSC_RC_BUF_THRESH_0        0x68
+#define DSC_RC_MIN_QP_0            0x78
+#define DSC_RC_MAX_QP_0            0x84
+#define DSC_RC_RANGE_BPG_OFFSETS_0 0x90
+
+/* DPU_DSC_CTL register offsets */
+#define DSC_CTL                    0x00
+#define DSC_CFG                    0x04
+#define DSC_DATA_IN_SWAP           0x08
+#define DSC_CLK_CTRL               0x0C
+
+static inline int _dsc_calc_ob_max_addr(struct dpu_hw_dsc *hw_dsc, int num_ss, bool native_422)
+{
+    int max_addr = 2400 / num_ss;
+
+    if ((hw_dsc->caps->features & BIT(DPU_DSC_NATIVE_422_EN)) && native_422)
+        max_addr /= 2;
+
+    return max_addr - 1;
+};
+
+static void dpu_hw_dsc_disable_1_2(struct dpu_hw_dsc *hw_dsc)
+{
+    struct dpu_hw_blk_reg_map *hw;
+    u32 offset;
+
+    if (!hw_dsc)
+        return;
+
+    hw = &hw_dsc->hw;
+    offset = hw_dsc->caps->sblk->ctl.base;
+    DPU_REG_WRITE(hw, offset + DSC_CFG, 0);
+
+    offset = hw_dsc->caps->sblk->enc.base;
+    DPU_REG_WRITE(hw, offset + ENC_DF_CTRL, 0);
+    DPU_REG_WRITE(hw, offset + DSC_MAIN_CONF, 0);
+}
+
+static void dpu_hw_dsc_config_1_2(struct dpu_hw_dsc *hw_dsc,
+                  struct drm_dsc_config *dsc,
+                  u32 mode,
+                  u32 initial_lines)
+{
+    struct dpu_hw_blk_reg_map *hw;
+    u32 offset;
+    u32 data = 0;
+    u32 det_thresh_flatness;
+    u32 num_active_ss_per_enc;
+    u32 bpp;
+
+    if (!hw_dsc || !dsc)
+        return;
+
+    hw = &hw_dsc->hw;
+
+    offset = hw_dsc->caps->sblk->enc.base;
+
+    if (mode & DSC_MODE_SPLIT_PANEL)
+        data |= BIT(0);
+
+    if (mode & DSC_MODE_MULTIPLEX)
+        data |= BIT(1);
+
+    num_active_ss_per_enc = dsc->slice_count;
+    if (mode & DSC_MODE_MULTIPLEX)
+        num_active_ss_per_enc = dsc->slice_count >> 1;
+
+    data |= (num_active_ss_per_enc & 0x3) << 7;
+
+    DPU_REG_WRITE(hw, DSC_CMN_MAIN_CNF, data);
+
+    data = (initial_lines & 0xff);
+
+    if (mode & DSC_MODE_VIDEO)
+        data |= BIT(9);
+
+    data |= (_dsc_calc_ob_max_addr(hw_dsc, num_active_ss_per_enc, dsc->native_422) << 18);
+
+    DPU_REG_WRITE(hw, offset + ENC_DF_CTRL, data);
+
+    data = (dsc->dsc_version_minor & 0xf) << 28;
+    if (dsc->dsc_version_minor == 0x2) {
+        if (dsc->native_422)
+            data |= BIT(22);
+        if (dsc->native_420)
+            data |= BIT(21);
+    }
+
+    bpp = dsc->bits_per_pixel;
+    /* as per hw requirement bpp should be programmed
+     * twice the actual value in case of 420 or 422 encoding
+     */
+    if (dsc->native_422 || dsc->native_420)
+        bpp = 2 * bpp;
+    data |= (dsc->block_pred_enable ? 1 : 0) << 20;
+    data |= bpp << 10;
+    data |= (dsc->line_buf_depth & 0xf) << 6;
+    data |= dsc->convert_rgb << 4;
+    data |= dsc->bits_per_component & 0xf;
+
+    DPU_REG_WRITE(hw, offset + DSC_MAIN_CONF, data);
+
+    data = (dsc->pic_width & 0xffff) |
+        ((dsc->pic_height & 0xffff) << 16);
+
+    DPU_REG_WRITE(hw, offset + DSC_PICTURE_SIZE, data);
+
+    data = (dsc->slice_width & 0xffff) |
+        ((dsc->slice_height & 0xffff) << 16);
+
+    DPU_REG_WRITE(hw, offset + DSC_SLICE_SIZE, data);
+
+    DPU_REG_WRITE(hw, offset + DSC_MISC_SIZE,
+            (dsc->slice_chunk_size) & 0xffff);
+
+    data = (dsc->initial_xmit_delay & 0xffff) |
+        ((dsc->initial_dec_delay & 0xffff) << 16);
+
+    DPU_REG_WRITE(hw, offset + DSC_HRD_DELAYS, data);
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_SCALE,
+            dsc->initial_scale_value & 0x3f);
+
+    data = (dsc->scale_increment_interval & 0xffff) |
+        ((dsc->scale_decrement_interval & 0x7ff) << 16);
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_SCALE_INC_DEC, data);
+
+    data = (dsc->first_line_bpg_offset & 0x1f) |
+        ((dsc->second_line_bpg_offset & 0x1f) << 5);
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_OFFSETS_1, data);
+
+    data = (dsc->nfl_bpg_offset & 0xffff) |
+        ((dsc->slice_bpg_offset & 0xffff) << 16);
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_OFFSETS_2, data);
+
+    data = (dsc->initial_offset & 0xffff) |
+        ((dsc->final_offset & 0xffff) << 16);
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_OFFSETS_3, data);
+
+    data = (dsc->nsl_bpg_offset & 0xffff) |
+        ((dsc->second_line_offset_adj & 0xffff) << 16);
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_OFFSETS_4, data);
+
+    data = (dsc->flatness_min_qp & 0x1f);
+    data |= (dsc->flatness_max_qp & 0x1f) << 5;
+
+    det_thresh_flatness = drm_dsc_calculate_flatness_det_thresh(dsc);
+    data |= (det_thresh_flatness & 0xff) << 10;
+
+    DPU_REG_WRITE(hw, offset + DSC_FLATNESS_QP, data);
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_MODEL_SIZE,
+            (dsc->rc_model_size) & 0xffff);
+
+    data = dsc->rc_edge_factor & 0xf;
+    data |= (dsc->rc_quant_incr_limit0 & 0x1f) << 8;
+    data |= (dsc->rc_quant_incr_limit1 & 0x1f) << 13;
+    data |= (dsc->rc_tgt_offset_high & 0xf) << 20;
+    data |= (dsc->rc_tgt_offset_low & 0xf) << 24;
+
+    DPU_REG_WRITE(hw, offset + DSC_RC_CONFIG, data);
+
+    /* program the dsc wrapper */
+    offset = hw_dsc->caps->sblk->ctl.base;
+
+    data = BIT(0); /* encoder enable */
+    if (dsc->native_422)
+        data |= BIT(8);
+    else if (dsc->native_420)
+        data |= BIT(9);
+    if (!dsc->convert_rgb)
+        data |= BIT(10);
+    if (dsc->bits_per_component == 8)
+        data |= BIT(11);
+    if (mode & DSC_MODE_SPLIT_PANEL)
+        data |= BIT(12);
+    if (mode & DSC_MODE_MULTIPLEX)
+        data |= BIT(13);
+    if (!(mode & DSC_MODE_VIDEO))
+        data |= BIT(17);
+
+    DPU_REG_WRITE(hw, offset + DSC_CFG, data);
+}
+
+static void dpu_hw_dsc_config_thresh_1_2(struct dpu_hw_dsc *hw_dsc,
+                    struct drm_dsc_config *dsc)
+{
+    struct dpu_hw_blk_reg_map *hw;
+    u32 offset, off;
+    int i, j = 0;
+    struct drm_dsc_rc_range_parameters *rc;
+    u32 data = 0, min_qp = 0, max_qp = 0, bpg_off = 0;
+
+    if (!hw_dsc || !dsc)
+        return;
+
+    offset = hw_dsc->caps->sblk->enc.base;
+
+    hw = &hw_dsc->hw;
+
+    rc = dsc->rc_range_params;
+
+    /*
+     * With BUF_THRESH -- 14 in total
+     * each register contains 4 thresh values with the last register
+     * containing only 2 thresh values
+     */
+    off = 0;
+    for (i = 0; i < DSC_NUM_BUF_RANGES - 1; i++) {
+        data |= dsc->rc_buf_thresh[i] << (8 * j);
+        j++;
+        if ((j == 4) || (i == DSC_NUM_BUF_RANGES - 2)) {
+            DPU_REG_WRITE(hw, offset + DSC_RC_BUF_THRESH_0 + off, data);
+            off += 4;
+            j = 0;
+            data = 0;
+        }
+    }

This is barely understandable code. The following line is much better:

DPU_REG_WRITE(hw, offset + DSC_RC_BUF_THRESH_0,
    (dsc->rc_buf_thresh[0] << 0) |
    (dsc->rc_buf_thresh[1] << 8) |
    (dsc->rc_buf_thresh[2] << 16) |
    (dsc->rc_buf_thresh[3] << 24));

etc.

Please unroll both loops.

+
+
+    /*
+     * with min/max_QP -- 5 bits each
+     * each register contains 5 min_qp or max_qp for total of 15
+     *
+     * With BPG_OFFSET -- 6 bits each
+     * each register contains 5 BPG_offset for total of 15
+     */
+    off = 0;
+    for (i = 0; i < DSC_NUM_BUF_RANGES; i++) {
+        min_qp |= rc[i].range_min_qp << (5 * j);
+        max_qp |= rc[i].range_max_qp << (5 * j);
+        bpg_off |= rc[i].range_bpg_offset << (6 * j);
+        j++;
+        if (j == 5) {
+            DPU_REG_WRITE(hw, offset + DSC_RC_MIN_QP_0 + off, min_qp);
+            DPU_REG_WRITE(hw, offset + DSC_RC_MAX_QP_0 + off, max_qp);
+            DPU_REG_WRITE(hw, offset + DSC_RC_RANGE_BPG_OFFSETS_0 + off, bpg_off);
+            off += 4;
+            j = 0;
+            min_qp = 0;
+            max_qp = 0;
+            bpg_off = 0;
+        }
+    }
+}
+
+static void dpu_hw_dsc_bind_pingpong_blk_1_2(
+        struct dpu_hw_dsc *hw_dsc,
+        bool enable,
+        const enum dpu_pingpong pp)
+{
+    struct dpu_hw_blk_reg_map *hw;
+    int offset;
+    int mux_cfg = 0xf; /* Disabled */
+
+    offset = hw_dsc->caps->sblk->ctl.base;
+
+    hw = &hw_dsc->hw;
+    if (enable)
+        mux_cfg = (pp - PINGPONG_0) & 0x7;
+
+    DPU_REG_WRITE(hw, offset + DSC_CTL, mux_cfg);
+}

Please refactor the existing bind_pingpong_blk() semantics to accept either a valid PINGPONG_n, or PINGPONG_NONE to disable the binding.

+
+static void _setup_dcs_ops_1_2(struct dpu_hw_dsc_ops *ops,
+        const unsigned long features)
+{
+    ops->dsc_disable = dpu_hw_dsc_disable_1_2;
+    ops->dsc_config = dpu_hw_dsc_config_1_2;
+    ops->dsc_config_thresh = dpu_hw_dsc_config_thresh_1_2;
+    ops->dsc_bind_pingpong_blk = dpu_hw_dsc_bind_pingpong_blk_1_2;
+}

Please inline the function.

+
+struct dpu_hw_dsc *dpu_hw_dsc_init_1_2(const struct dpu_dsc_cfg *cfg,
+                   void __iomem *addr)
+{
+    struct dpu_hw_dsc *c;
+
+    c = kzalloc(sizeof(*c), GFP_KERNEL);
+    if (!c)
+        return ERR_PTR(-ENOMEM);
+
+    c->hw.blk_addr = addr + cfg->base;
+    c->hw.log_mask = DPU_DBG_MASK_DSC;
+
+    c->idx = cfg->id;
+    c->caps = cfg;
+    _setup_dcs_ops_1_2(&c->ops, c->caps->features);
+
+    return c;
+}
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
index 3452f88..b2f618f6 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
@@ -1,6 +1,7 @@
  // SPDX-License-Identifier: GPL-2.0-only
  /*
   * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
   */
  #define pr_fmt(fmt)    "[drm:%s] " fmt, __func__
@@ -250,7 +251,11 @@ int dpu_rm_init(struct dpu_rm *rm,
          struct dpu_hw_dsc *hw;
          const struct dpu_dsc_cfg *dsc = &cat->dsc[i];
-        hw = dpu_hw_dsc_init(dsc, mmio);
+        if (test_bit(DPU_DSC_HW_REV_1_2, &dsc->features))
+            hw = dpu_hw_dsc_init_1_2(dsc, mmio);
+        else
+            hw = dpu_hw_dsc_init(dsc, mmio);
+
          if (IS_ERR_OR_NULL(hw)) {
              rc = PTR_ERR(hw);
              DPU_ERROR("failed dsc object creation: err %d\n", rc);