From 4d054ca9ad01004901f3ba988d77f7d298819c12 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Mon, 1 Aug 2022 15:15:55 +0200 Subject: [PATCH] drm: bridge: icn6211: Add and use hs_rate and lp_rate Fill in hs_rate and lp_rate to struct mipi_dsi_device for this bridge and adjust DSI input frequency calculations such that they expect the DSI host to configure HS clock according to hs_rate. This is an optimization for the DSI burst mode case. In case the DSI device supports DSI burst mode, it is recommended to operate the DSI interface at the highest possible HS clock frequency which the DSI device supports. This permits the DSI host to send as short as possible bursts of data on the DSI link and keep the DSI data lanes in LP mode otherwise, which reduces power consumption. Signed-off-by: Marek Vasut Cc: Jagan Teki Cc: Laurent Pinchart Cc: Linus Walleij Cc: Robert Foss Cc: Sam Ravnborg Cc: dri-devel@lists.freedesktop.org Signed-off-by: Linus Walleij Link: https://patchwork.freedesktop.org/patch/msgid/20220801131555.182969-1-marex@denx.de --- drivers/gpu/drm/bridge/chipone-icn6211.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/bridge/chipone-icn6211.c b/drivers/gpu/drm/bridge/chipone-icn6211.c index b07d2d1..5db0224d 100644 --- a/drivers/gpu/drm/bridge/chipone-icn6211.c +++ b/drivers/gpu/drm/bridge/chipone-icn6211.c @@ -259,7 +259,7 @@ static void chipone_configure_pll(struct chipone *icn, /* * DSI byte clock frequency (input into PLL) is calculated as: - * DSI_CLK = mode clock * bpp / dsi_data_lanes / 8 + * DSI_CLK = HS clock / 4 * * DPI pixel clock frequency (output from PLL) is mode clock. * @@ -273,8 +273,7 @@ static void chipone_configure_pll(struct chipone *icn, * It seems the PLL input clock after applying P pre-divider have * to be lower than 20 MHz. */ - fin = mode_clock * mipi_dsi_pixel_format_to_bpp(icn->dsi->format) / - icn->dsi->lanes / 8; /* in Hz */ + fin = icn->dsi->hs_rate / 4; /* in Hz */ /* Minimum value of P predivider for PLL input in 5..20 MHz */ p_min = clamp(DIV_ROUND_UP(fin, 20000000), 1U, 31U); @@ -515,6 +514,8 @@ static int chipone_dsi_attach(struct chipone *icn) dsi->format = MIPI_DSI_FMT_RGB888; dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST | MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_NO_EOT_PACKET; + dsi->hs_rate = 500000000; + dsi->lp_rate = 16000000; ret = mipi_dsi_attach(dsi); if (ret < 0) -- 2.7.4