Hi Dragan，
At 2024-07-04 07:32:02, "Dragan Simic" <dsi...@manjaro.org> wrote:
>After the additional firmware-related module information was introduced by
>the commit c0677e41a47f ("drm/rockchip: cdn-dp-core: add MODULE_FIRMWARE
>macro"), there's no longer need for the firmware-loading workarounds whose
>sole purpose was to prevent the missing firmware blob in an initial ramdisk
>from causing driver initialization to fail. Thus, delete the workarounds,
>which removes a sizable chunk of redundant code.
What would happen if there was no ramdisk? And the firmware is in rootfs ？
For example： A buildroot based tiny embedded system。
>
>Various utilities used by Linux distributions to generate initial ramdisks
>need to obey the firmware-related module information, so we can rely on the
>firmware blob being present in the generated initial ramdisks.
>
>Signed-off-by: Dragan Simic <dsi...@manjaro.org>
>---
> drivers/gpu/drm/rockchip/cdn-dp-core.c | 53 +++++---------------------
> 1 file changed, 10 insertions(+), 43 deletions(-)
>
>diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.c
>b/drivers/gpu/drm/rockchip/cdn-dp-core.c
>index bd7aa891b839..e1a7c6a1172b 100644
>--- a/drivers/gpu/drm/rockchip/cdn-dp-core.c
>+++ b/drivers/gpu/drm/rockchip/cdn-dp-core.c
>@@ -44,9 +44,9 @@ static inline struct cdn_dp_device *encoder_to_dp(struct
>drm_encoder *encoder)
> #define DPTX_HPD_DEL (2 << 12)
> #define DPTX_HPD_SEL_MASK (3 << 28)
>
>-#define CDN_FW_TIMEOUT_MS (64 * 1000)
> #define CDN_DPCD_TIMEOUT_MS 5000
> #define CDN_DP_FIRMWARE "rockchip/dptx.bin"
>+
> MODULE_FIRMWARE(CDN_DP_FIRMWARE);
>
> struct cdn_dp_data {
>@@ -909,61 +909,28 @@ static int cdn_dp_audio_codec_init(struct cdn_dp_device
>*dp,
> return PTR_ERR_OR_ZERO(dp->audio_pdev);
> }
>
>-static int cdn_dp_request_firmware(struct cdn_dp_device *dp)
>-{
>- int ret;
>- unsigned long timeout = jiffies + msecs_to_jiffies(CDN_FW_TIMEOUT_MS);
>- unsigned long sleep = 1000;
>-
>- WARN_ON(!mutex_is_locked(&dp->lock));
>-
>- if (dp->fw_loaded)
>- return 0;
>-
>- /* Drop the lock before getting the firmware to avoid blocking boot */
>- mutex_unlock(&dp->lock);
>-
>- while (time_before(jiffies, timeout)) {
>- ret = request_firmware(&dp->fw, CDN_DP_FIRMWARE, dp->dev);
>- if (ret == -ENOENT) {
>- msleep(sleep);
>- sleep *= 2;
>- continue;
>- } else if (ret) {
>- DRM_DEV_ERROR(dp->dev,
>- "failed to request firmware: %d\n", ret);
>- goto out;
>- }
>-
>- dp->fw_loaded = true;
>- ret = 0;
>- goto out;
>- }
>-
>- DRM_DEV_ERROR(dp->dev, "Timed out trying to load firmware\n");
>- ret = -ETIMEDOUT;
>-out:
>- mutex_lock(&dp->lock);
>- return ret;
>-}
>-
> static void cdn_dp_pd_event_work(struct work_struct *work)
> {
> struct cdn_dp_device *dp = container_of(work, struct cdn_dp_device,
> event_work);
> struct drm_connector *connector = &dp->connector;
> enum drm_connector_status old_status;
>-
> int ret;
>
> mutex_lock(&dp->lock);
>
> if (dp->suspended)
> goto out;
>
>- ret = cdn_dp_request_firmware(dp);
>- if (ret)
>- goto out;
>+ if (!dp->fw_loaded) {
>+ ret = request_firmware(&dp->fw, CDN_DP_FIRMWARE, dp->dev);
>+ if (ret) {
>+ DRM_DEV_ERROR(dp->dev, "Loading firmware failed: %d\n",
>ret);
>+ goto out;
>+ }
>+
>+ dp->fw_loaded = true;
>+ }
>
> dp->connected = true;
>
