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authorMarek Vasut <marex@denx.de>2024-01-18 23:02:31 +0100
committerRobert Foss <rfoss@kernel.org>2024-01-23 12:18:01 +0100
commitf86ae204bec4e72f14f7d4fd586d7ef9729614dc (patch)
tree46d8e723cd8c7fb636078484426bf39e06da870b /drivers/gpu/drm/bridge/tc358767.c
parentvideo/nomodeset: Select nomodeset= parameter with CONFIG_VIDEO (diff)
downloadlinux-f86ae204bec4e72f14f7d4fd586d7ef9729614dc.tar.xz
linux-f86ae204bec4e72f14f7d4fd586d7ef9729614dc.zip
drm/bridge: tc358767: Limit the Pixel PLL input range
According to new configuration spreadsheet from Toshiba for TC9595, the Pixel PLL input clock have to be in range 6..40 MHz. The sheet calculates those PLL input clock as reference clock divided by both pre-dividers. Add the extra limit. Signed-off-by: Marek Vasut <marex@denx.de> Reviewed-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Robert Foss <rfoss@kernel.org> Link: https://patchwork.freedesktop.org/patch/msgid/20240118220243.203655-1-marex@denx.de
Diffstat (limited to 'drivers/gpu/drm/bridge/tc358767.c')
-rw-r--r--drivers/gpu/drm/bridge/tc358767.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
index eb0d82a91cb9..f10ba91dc252 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -617,9 +617,14 @@ static int tc_pxl_pll_en(struct tc_data *tc, u32 refclk, u32 pixelclock)
continue;
for (i_post = 0; i_post < ARRAY_SIZE(ext_div); i_post++) {
for (div = 1; div <= 16; div++) {
- u32 clk;
+ u32 clk, iclk;
u64 tmp;
+ /* PCLK PLL input unit clock ... 6..40 MHz */
+ iclk = refclk / (div * ext_div[i_pre]);
+ if (iclk < 6000000 || iclk > 40000000)
+ continue;
+
tmp = pixelclock * ext_div[i_pre] *
ext_div[i_post] * div;
do_div(tmp, refclk);