openwrt/target/linux/brcm2708/patches-4.4/0285-drm-vc4-Bring-HDMI-up-from-power-off-if-necessary.patch
Álvaro Fernández Rojas 011f2c26f1 brcm2708: update linux 4.4 patches to latest version
As usual these patches were extracted and rebased from the raspberry pi repo:
https://github.com/raspberrypi/linux/tree/rpi-4.4.y

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2016-12-04 12:32:04 +01:00

73 lines
2.3 KiB
Diff

From fdd5a9166e76db86360c19da7917cd0aab407b85 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Fri, 12 Feb 2016 14:15:14 -0800
Subject: [PATCH] drm/vc4: Bring HDMI up from power off if necessary.
If the firmware hadn't brought up HDMI for us, we need to do its
power-on reset sequence (reset HD and and clear its STANDBY bits,
reset HDMI, and leave the PHY disabled).
Signed-off-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit 851479ad5927b7b1aa141ca9dedb897a7bce2b1d)
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 29 ++++++++++++++++++++++++++++-
drivers/gpu/drm/vc4/vc4_regs.h | 2 ++
2 files changed, 30 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -497,6 +497,16 @@ static int vc4_hdmi_bind(struct device *
goto err_put_i2c;
}
+ /* This is the rate that is set by the firmware. The number
+ * needs to be a bit higher than the pixel clock rate
+ * (generally 148.5Mhz).
+ */
+ ret = clk_set_rate(hdmi->hsm_clock, 163682864);
+ if (ret) {
+ DRM_ERROR("Failed to set HSM clock rate: %d\n", ret);
+ goto err_unprepare_pix;
+ }
+
ret = clk_prepare_enable(hdmi->hsm_clock);
if (ret) {
DRM_ERROR("Failed to turn on HDMI state machine clock: %d\n",
@@ -518,7 +528,24 @@ static int vc4_hdmi_bind(struct device *
vc4->hdmi = hdmi;
/* HDMI core must be enabled. */
- WARN_ON_ONCE((HD_READ(VC4_HD_M_CTL) & VC4_HD_M_ENABLE) == 0);
+ if (!(HD_READ(VC4_HD_M_CTL) & VC4_HD_M_ENABLE)) {
+ HD_WRITE(VC4_HD_M_CTL, VC4_HD_M_SW_RST);
+ udelay(1);
+ HD_WRITE(VC4_HD_M_CTL, 0);
+
+ HD_WRITE(VC4_HD_M_CTL, VC4_HD_M_ENABLE);
+
+ HDMI_WRITE(VC4_HDMI_SW_RESET_CONTROL,
+ VC4_HDMI_SW_RESET_HDMI |
+ VC4_HDMI_SW_RESET_FORMAT_DETECT);
+
+ HDMI_WRITE(VC4_HDMI_SW_RESET_CONTROL, 0);
+
+ /* PHY should be in reset, like
+ * vc4_hdmi_encoder_disable() does.
+ */
+ HDMI_WRITE(VC4_HDMI_TX_PHY_RESET_CTL, 0xf << 16);
+ }
drm_encoder_init(drm, hdmi->encoder, &vc4_hdmi_encoder_funcs,
DRM_MODE_ENCODER_TMDS);
--- a/drivers/gpu/drm/vc4/vc4_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_regs.h
@@ -456,6 +456,8 @@
#define VC4_HDMI_TX_PHY_RESET_CTL 0x2c0
#define VC4_HD_M_CTL 0x00c
+# define VC4_HD_M_REGISTER_FILE_STANDBY (3 << 6)
+# define VC4_HD_M_RAM_STANDBY (3 << 4)
# define VC4_HD_M_SW_RST BIT(2)
# define VC4_HD_M_ENABLE BIT(0)