On Thu, 2025-08-28 at 15:20 +0300, Jani Nikula wrote:
> Prefer generic poll helpers over i915 custom helpers.
>
> The functional change is losing the exponentially growing sleep of
> wait_for(), which used to be 10, 20, 40, ..., 640, and 1280 us.
>
> Use an arbitrary constant 500 us sleep instead. The timeout remains
> at
> 20 ms.
>
> Signed-off-by: Jani Nikula <jani.nik...@intel.com>
Reviewed-by: Jouni Högander <jouni.hogan...@intel.com>
> ---
> drivers/gpu/drm/i915/display/vlv_dsi_pll.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/vlv_dsi_pll.c
> b/drivers/gpu/drm/i915/display/vlv_dsi_pll.c
> index 83afe1315e96..f078b9cda96c 100644
> --- a/drivers/gpu/drm/i915/display/vlv_dsi_pll.c
> +++ b/drivers/gpu/drm/i915/display/vlv_dsi_pll.c
> @@ -25,12 +25,12 @@
> * Yogesh Mohan Marimuthu <yogesh.mohan.marimu...@intel.com>
> */
>
> +#include <linux/iopoll.h>
> #include <linux/kernel.h>
> #include <linux/string_helpers.h>
>
> #include <drm/drm_print.h>
>
> -#include "i915_utils.h"
> #include "intel_de.h"
> #include "intel_display_types.h"
> #include "intel_dsi.h"
> @@ -214,6 +214,8 @@ void vlv_dsi_pll_enable(struct intel_encoder
> *encoder,
> const struct intel_crtc_state *config)
> {
> struct intel_display *display = to_intel_display(encoder);
> + u32 val;
> + int ret;
>
> drm_dbg_kms(display->drm, "\n");
>
> @@ -231,9 +233,10 @@ void vlv_dsi_pll_enable(struct intel_encoder
> *encoder,
>
> vlv_cck_write(display->drm, CCK_REG_DSI_PLL_CONTROL, config-
> >dsi_pll.ctrl);
>
> - if (wait_for(vlv_cck_read(display->drm,
> CCK_REG_DSI_PLL_CONTROL) &
> - DSI_PLL_LOCK, 20)) {
> -
> + ret = poll_timeout_us(val = vlv_cck_read(display->drm,
> CCK_REG_DSI_PLL_CONTROL),
> + val & DSI_PLL_LOCK,
> + 500, 20 * 1000, false);
> + if (ret) {
> vlv_cck_put(display->drm);
> drm_err(display->drm, "DSI PLL lock failed\n");
> return;
