Hi all,
Friendly ping on this patch.
Regards,
Pin-yen
On Thu, Nov 3, 2022 at 5:13 PM allen <allen.chen@xxxxxxxxxx> wrote:
>
> From: allen chen <allen.chen@xxxxxxxxxx>
>
> Add driver to read data-lanes and link-frequencies from dt property to
> restrict output bandwidth.
>
> Signed-off-by: Allen chen <allen.chen@xxxxxxxxxx>
> Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/bridge/ite-it6505.c | 80 +++++++++++++++++++++++++++--
> 1 file changed, 77 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
> index a4302492cf8df..ed4536cde3140 100644
> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> @@ -437,6 +437,8 @@ struct it6505 {
> bool powered;
> bool hpd_state;
> u32 afe_setting;
> + u32 max_dpi_pixel_clock;
> + u32 max_lane_count;
> enum hdcp_state hdcp_status;
> struct delayed_work hdcp_work;
> struct work_struct hdcp_wait_ksv_list;
> @@ -1476,7 +1478,8 @@ static void it6505_parse_link_capabilities(struct it6505 *it6505)
> it6505->lane_count = link->num_lanes;
> DRM_DEV_DEBUG_DRIVER(dev, "Sink support %d lanes training",
> it6505->lane_count);
> - it6505->lane_count = min_t(int, it6505->lane_count, MAX_LANE_COUNT);
> + it6505->lane_count = min_t(int, it6505->lane_count,
> + it6505->max_lane_count);
>
> it6505->branch_device = drm_dp_is_branch(it6505->dpcd);
> DRM_DEV_DEBUG_DRIVER(dev, "Sink %sbranch device",
> @@ -2912,7 +2915,7 @@ it6505_bridge_mode_valid(struct drm_bridge *bridge,
> if (mode->flags & DRM_MODE_FLAG_INTERLACE)
> return MODE_NO_INTERLACE;
>
> - if (mode->clock > DPI_PIXEL_CLK_MAX)
> + if (mode->clock > it6505->max_dpi_pixel_clock)
> return MODE_CLOCK_HIGH;
>
> it6505->video_info.clock = mode->clock;
> @@ -3099,10 +3102,32 @@ static int it6505_init_pdata(struct it6505 *it6505)
> return 0;
> }
>
> +static int it6505_get_data_lanes_count(const struct device_node *endpoint,
> + const unsigned int min,
> + const unsigned int max)
> +{
> + int ret;
> +
> + ret = of_property_count_u32_elems(endpoint, "data-lanes");
> + if (ret < 0)
> + return ret;
> +
> + if (ret < min || ret > max)
> + return -EINVAL;
> +
> + return ret;
> +}
> +
> static void it6505_parse_dt(struct it6505 *it6505)
> {
> struct device *dev = &it6505->client->dev;
> + struct device_node *np = dev->of_node, *ep = NULL;
> + int len;
> + u64 link_frequencies;
> + u32 data_lanes[4];
> u32 *afe_setting = &it6505->afe_setting;
> + u32 *max_lane_count = &it6505->max_lane_count;
> + u32 *max_dpi_pixel_clock = &it6505->max_dpi_pixel_clock;
>
> it6505->lane_swap_disabled =
> device_property_read_bool(dev, "no-laneswap");
> @@ -3118,7 +3143,56 @@ static void it6505_parse_dt(struct it6505 *it6505)
> } else {
> *afe_setting = 0;
> }
> - DRM_DEV_DEBUG_DRIVER(dev, "using afe_setting: %d", *afe_setting);
> +
> + ep = of_graph_get_endpoint_by_regs(np, 1, 0);
> + of_node_put(ep);
> +
> + if (ep) {
> + len = it6505_get_data_lanes_count(ep, 1, 4);
> +
> + if (len > 0 && len != 3) {
> + of_property_read_u32_array(ep, "data-lanes",
> + data_lanes, len);
> + *max_lane_count = len;
> + } else {
> + *max_lane_count = MAX_LANE_COUNT;
> + dev_err(dev, "error data-lanes, use default");
> + }
> + } else {
> + *max_lane_count = MAX_LANE_COUNT;
> + dev_err(dev, "error endpoint, use default");
> + }
> +
> + ep = of_graph_get_endpoint_by_regs(np, 0, 0);
> + of_node_put(ep);
> +
> + if (ep) {
> + len = of_property_read_variable_u64_array(ep,
> + "link-frequencies",
> + &link_frequencies, 0,
> + 1);
> + if (len >= 0) {
> + do_div(link_frequencies, 1000);
> + if (link_frequencies > 297000) {
> + dev_err(dev,
> + "max pixel clock error, use default");
> + *max_dpi_pixel_clock = DPI_PIXEL_CLK_MAX;
> + } else {
> + *max_dpi_pixel_clock = link_frequencies;
> + }
> + } else {
> + dev_err(dev, "error link frequencies, use default");
> + *max_dpi_pixel_clock = DPI_PIXEL_CLK_MAX;
> + }
> + } else {
> + dev_err(dev, "error endpoint, use default");
> + *max_dpi_pixel_clock = DPI_PIXEL_CLK_MAX;
> + }
> +
> + DRM_DEV_DEBUG_DRIVER(dev, "using afe_setting: %u, max_lane_count: %u",
> + it6505->afe_setting, it6505->max_lane_count);
> + DRM_DEV_DEBUG_DRIVER(dev, "using max_dpi_pixel_clock: %u kHz",
> + it6505->max_dpi_pixel_clock);
> }
>
> static ssize_t receive_timing_debugfs_show(struct file *file, char __user *buf,
> --
> 2.25.1
>
