On Mon, Dec 2, 2019 at 5:48 AM Chandan Uddaraju chandanu@codeaurora.org wrote:

Add the needed displayPort files to enable DP driver on msm target.

"dp_display" module is the main module that calls into other sub-modules. "dp_drm" file represents the interface between DRM framework and DP driver.

changes in v2: -- Update copyright markings on all relevant files. -- Change pr_err() to DRM_ERROR() -- Use APIs directly instead of function pointers. -- Use drm_display_mode structure to store link parameters in the driver. -- Use macros for register definitions instead of hardcoded values. -- Replace writel_relaxed/readl_relaxed with writel/readl and remove memory barriers. -- Remove unnecessary NULL checks. -- Use drm helper functions for dpcd read/write. -- Use DRM_DEBUG_DP for debug msgs.

changes in V3: -- Removed changes in dpu_io_util.[ch] -- Added locking around "is_connected" flag and removed atomic_set() -- Removed the argument validation checks in all the static functions except initialization functions and few API calls across msm/dp files -- Removed hardcoded values for register reads/writes -- Removed vreg related generic structures. -- Added return values where ever necessary. -- Updated dp_ctrl_on function. -- Calling the ctrl specific catalog functions directly instead of function pointers. -- Added seperate change that adds standard value in drm_dp_helper file. -- Added separate change in this list that is used to initialize displayport in DPU driver. -- Added change to use drm_dp_get_adjust_request_voltage() function.

Signed-off-by: Chandan Uddaraju chandanu@codeaurora.org

[snip]

+void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog,

•                                   u32 rate, u32 stream_rate_khz,
  

•                                   bool fixed_nvid)
  

+{

•   u32 pixel_m, pixel_n;
  

•   u32 mvid, nvid;
  

•   u64 mvid_calc;
  

•   struct dp_catalog_private *catalog = container_of(dp_catalog,
  

•                           struct dp_catalog_private, dp_catalog);
  

•   if (fixed_nvid) {
  

•           nvid = DP_LINK_CONSTANT_N_VALUE;
  

•           DRM_DEBUG_DP("use fixed NVID=0x%x\n", nvid);
  

•           /*
  

•            * For intermediate results, use 64 bit arithmetic to avoid
  

•            * loss of precision.
  

•            */
  

•           mvid_calc = (u64) stream_rate_khz * nvid;
  

•           mvid_calc = div_u64(mvid_calc, rate);
  

•           /*
  

•            * truncate back to 32 bits as this final divided value will
  

•            * always be within the range of a 32 bit unsigned int.
  

•            */
  

•           mvid = (u32) mvid_calc;
  

•           DRM_DEBUG_DP("link rate=%dkbps, stream_rate_khz=%uKhz",
  

•                   rate, stream_rate_khz);
  

•   } else {
  

•           pixel_m = dp_read_cc(catalog, MMSS_DP_PIXEL_M);
  

•           pixel_n = dp_read_cc(catalog, MMSS_DP_PIXEL_N);
  

Can we just calculate m/n from the rate instead. That gets rid of having to ioremap() the dispcc region, which is really ugly.

BR, -R

•           DRM_DEBUG_DP("pixel_m=0x%x, pixel_n=0x%x\n", pixel_m, pixel_n);
  

•           mvid = (pixel_m & 0xFFFF) * 5;
  

•           nvid = (0xFFFF & (~pixel_n)) + (pixel_m & 0xFFFF);
  

•           DRM_DEBUG_DP("rate = %d\n", rate);
  

•           switch (drm_dp_link_rate_to_bw_code(rate)) {
  

•           case DP_LINK_BW_5_4:
  

•                   nvid *= 2;
  

•                   break;
  

•           case DP_LINK_BW_8_1:
  

•                   nvid *= 3;
  

•                   break;
  

•           default:
  

•                   break;
  

•           }
  

•   }
  

•   DRM_DEBUG_DP("mvid=0x%x, nvid=0x%x\n", mvid, nvid);
  

•   dp_write_link(catalog, REG_DP_SOFTWARE_MVID, mvid);
  

•   dp_write_link(catalog, REG_DP_SOFTWARE_NVID, nvid);
  

+}