From 3e4c31e8f70251732529a10934355084c7fab0ac Mon Sep 17 00:00:00 2001 From: Anitha Chrisanthus Date: Tue, 15 Dec 2020 11:13:09 -0800 Subject: drm/kmb: Work around for higher system clock Use a different value for system clock offset in the ppl/llp ratio calculations for clocks higher than 500 Mhz. Fixes: 98521f4d4b4c ("drm/kmb: Mipi DSI part of the display driver") Signed-off-by: Anitha Chrisanthus Acked-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20211013233632.471892-1-anitha.chrisanthus@intel.com Signed-off-by: Maarten Lankhorst --- drivers/gpu/drm/kmb/kmb_dsi.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/kmb/kmb_dsi.c') diff --git a/drivers/gpu/drm/kmb/kmb_dsi.c b/drivers/gpu/drm/kmb/kmb_dsi.c index 1793cd31b117..86e8e7943e89 100644 --- a/drivers/gpu/drm/kmb/kmb_dsi.c +++ b/drivers/gpu/drm/kmb/kmb_dsi.c @@ -482,6 +482,10 @@ static u32 mipi_tx_fg_section_cfg(struct kmb_dsi *kmb_dsi, return 0; } +#define CLK_DIFF_LOW 50 +#define CLK_DIFF_HI 60 +#define SYSCLK_500 500 + static void mipi_tx_fg_cfg_regs(struct kmb_dsi *kmb_dsi, u8 frame_gen, struct mipi_tx_frame_timing_cfg *fg_cfg) { @@ -492,7 +496,12 @@ static void mipi_tx_fg_cfg_regs(struct kmb_dsi *kmb_dsi, u8 frame_gen, /* 500 Mhz system clock minus 50 to account for the difference in * MIPI clock speed in RTL tests */ - sysclk = kmb_dsi->sys_clk_mhz - 50; + if (kmb_dsi->sys_clk_mhz == SYSCLK_500) { + sysclk = kmb_dsi->sys_clk_mhz - CLK_DIFF_LOW; + } else { + /* 700 Mhz clk*/ + sysclk = kmb_dsi->sys_clk_mhz - CLK_DIFF_HI; + } /* PPL-Pixel Packing Layer, LLP-Low Level Protocol * Frame genartor timing parameters are clocked on the system clock, -- cgit v1.2.3