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keydata= xsBNBE1ZBs8BCAD78xVLsXPwV/2qQx2FaO/7mhWL0Qodw8UcQJnkrWmgTFRobtTWxuRx8WWP GTjuhvbleoQ5Cxjr+v+1ARGCH46MxFP5DwauzPekwJUD5QKZlaw/bURTLmS2id5wWi3lqVH4 BVF2WzvGyyeV1o4RTCYDnZ9VLLylJ9bneEaIs/7cjCEbipGGFlfIML3sfqnIvMAxIMZrvcl9 qPV2k+KQ7q+aXavU5W+yLNn7QtXUB530Zlk/d2ETgzQ5FLYYnUDAaRl+8JUTjc0CNOTpCeik 80TZcE6f8M76Xa6yU8VcNko94Ck7iB4vj70q76P/J7kt98hklrr85/3NU3oti3nrIHmHABEB AAHNKk5laWwgQXJtc3Ryb25nIDxuZWlsLmFybXN0cm9uZ0BsaW5hcm8ub3JnPsLAkQQTAQoA OwIbIwULCQgHAwUVCgkICwUWAgMBAAIeAQIXgBYhBInsPQWERiF0UPIoSBaat7Gkz/iuBQJk Q5wSAhkBAAoJEBaat7Gkz/iuyhMIANiD94qDtUTJRfEW6GwXmtKWwl/mvqQtaTtZID2dos04 YqBbshiJbejgVJjy+HODcNUIKBB3PSLaln4ltdsV73SBcwUNdzebfKspAQunCM22Mn6FBIxQ GizsMLcP/0FX4en9NaKGfK6ZdKK6kN1GR9YffMJd2P08EO8mHowmSRe/ExAODhAs9W7XXExw UNCY4pVJyRPpEhv373vvff60bHxc1k/FF9WaPscMt7hlkbFLUs85kHtQAmr8pV5Hy9ezsSRa GzJmiVclkPc2BY592IGBXRDQ38urXeM4nfhhvqA50b/nAEXc6FzqgXqDkEIwR66/Gbp0t3+r yQzpKRyQif3OwE0ETVkGzwEIALyKDN/OGURaHBVzwjgYq+ZtifvekdrSNl8TIDH8g1xicBYp QTbPn6bbSZbdvfeQPNCcD4/EhXZuhQXMcoJsQQQnO4vwVULmPGgtGf8PVc7dxKOeta+qUh6+ SRh3vIcAUFHDT3f/Zdspz+e2E0hPV2hiSvICLk11qO6cyJE13zeNFoeY3ggrKY+IzbFomIZY 4yG6xI99NIPEVE9lNBXBKIlewIyVlkOaYvJWSV+p5gdJXOvScNN1epm5YHmf9aE2ZjnqZGoM Mtsyw18YoX9BqMFInxqYQQ3j/HpVgTSvmo5ea5qQDDUaCsaTf8UeDcwYOtgI8iL4oHcsGtUX oUk33HEAEQEAAcLAXwQYAQIACQUCTVkGzwIbDAAKCRAWmrexpM/4rrXiB/sGbkQ6itMrAIfn M7IbRuiSZS1unlySUVYu3SD6YBYnNi3G5EpbwfBNuT3H8//rVvtOFK4OD8cRYkxXRQmTvqa3 3eDIHu/zr1HMKErm+2SD6PO9umRef8V82o2oaCLvf4WeIssFjwB0b6a12opuRP7yo3E3gTCS KmbUuLv1CtxKQF+fUV1cVaTPMyT25Od+RC1K+iOR0F54oUJvJeq7fUzbn/KdlhA8XPGzwGRy 4zcsPWvwnXgfe5tk680fEKZVwOZKIEuJC3v+/yZpQzDvGYJvbyix0lHnrCzq43WefRHI5XTT QbM0WUIBIcGmq38+OgUsMYu4NzLu7uZFAcmp6h8g Organization: Linaro In-Reply-To: <20240907-hdmi-tolerance-v2-1-b9d7abd89f5c@codewreck.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 07/09/2024 07:54, Dominique Martinet wrote: > From: Dominique Martinet > > This allows the hdmi driver to pick e.g. 64.8MHz instead of 65Mhz when we > cannot output the exact frequency, enabling the imx8mp HDMI output to > support more modes > > Tested-by: Adam Ford #imx8mp-beacon > Reviewed-by: Frieder Schrempf > Tested-by: Frieder Schrempf > Signed-off-by: Dominique Martinet > --- > Changes in v2: > - Improve comment about the tolerance > - Link to v1: https://lore.kernel.org/r/20240904083103.1257480-1-dominique.martinet@atmark-techno.com > --- > drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c b/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c > index 13bc570c5473..200d65184159 100644 > --- a/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c > +++ b/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-tx.c > @@ -23,6 +23,7 @@ imx8mp_hdmi_mode_valid(struct dw_hdmi *dw_hdmi, void *data, > const struct drm_display_mode *mode) > { > struct imx8mp_hdmi *hdmi = (struct imx8mp_hdmi *)data; > + long round_rate; > > if (mode->clock < 13500) > return MODE_CLOCK_LOW; > @@ -30,8 +31,14 @@ imx8mp_hdmi_mode_valid(struct dw_hdmi *dw_hdmi, void *data, > if (mode->clock > 297000) > return MODE_CLOCK_HIGH; > > - if (clk_round_rate(hdmi->pixclk, mode->clock * 1000) != > - mode->clock * 1000) > + round_rate = clk_round_rate(hdmi->pixclk, mode->clock * 1000); > + /* imx8mp's pixel clock generator (fsl-samsung-hdmi) cannot generate > + * all possible frequencies, so allow some tolerance to support more > + * modes. > + * Allow 0.5% difference allowed in various standards (VESA, CEA861) > + * 0.5% = 5/1000 tolerance (mode->clock is 1/1000) > + */ > + if (abs(round_rate - mode->clock * 1000) > mode->clock * 5) > return MODE_CLOCK_RANGE; > > /* We don't support double-clocked and Interlaced modes */ > > --- > base-commit: 67784a74e258a467225f0e68335df77acd67b7ab > change-id: 20240907-hdmi-tolerance-4d83074a4517 > > Best regards, Reviewed-by: Neil Armstrong