From ac3f918d5a069f1c34c6e0d39cccb0e9c8ac9334 Mon Sep 17 00:00:00 2001 From: Thomas Richter Date: Sat, 30 May 2015 20:25:53 +0200 Subject: [PATCH] Fix resume from suspend on IBM X30 This patch fixes the resume from suspend-to-ram on the IBM X30 laptop. The problem is caused by the Bios missing to re-initialize the iVCH registers, especially the PLL registers. This patch records the iVCH registers during initialization, and re-installs this register set when resuming. Signed-off-by: Thomas Richter Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/dvo_ivch.c | 63 +++++++++++++++++++++++++++++---- 1 file changed, 57 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/dvo_ivch.c b/drivers/gpu/drm/i915/dvo_ivch.c index 89b08a896d20..732ce8785945 100644 --- a/drivers/gpu/drm/i915/dvo_ivch.c +++ b/drivers/gpu/drm/i915/dvo_ivch.c @@ -22,6 +22,7 @@ * * Authors: * Eric Anholt + * Thomas Richter * * Minor modifications (Dithering enable): * Thomas Richter @@ -90,7 +91,7 @@ /* * LCD Vertical Display Size */ -#define VR21 0x20 +#define VR21 0x21 /* * Panel power down status @@ -155,16 +156,33 @@ # define VR8F_POWER_MASK (0x3c) # define VR8F_POWER_POS (2) +/* Some Bios implementations do not restore the DVO state upon + * resume from standby. Thus, this driver has to handle it + * instead. The following list contains all registers that + * require saving. + */ +static const uint16_t backup_addresses[] = { + 0x11, 0x12, + 0x18, 0x19, 0x1a, 0x1f, + 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, + 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, + 0x8e, 0x8f, + 0x10 /* this must come last */ +}; + struct ivch_priv { bool quiet; uint16_t width, height; + + /* Register backup */ + + uint16_t reg_backup[ARRAY_SIZE(backup_addresses)]; }; static void ivch_dump_regs(struct intel_dvo_device *dvo); - /** * Reads a register on the ivch. * @@ -246,6 +264,7 @@ static bool ivch_init(struct intel_dvo_device *dvo, { struct ivch_priv *priv; uint16_t temp; + int i; priv = kzalloc(sizeof(struct ivch_priv), GFP_KERNEL); if (priv == NULL) @@ -273,6 +292,14 @@ static bool ivch_init(struct intel_dvo_device *dvo, ivch_read(dvo, VR20, &priv->width); ivch_read(dvo, VR21, &priv->height); + /* Make a backup of the registers to be able to restore them + * upon suspend. + */ + for (i = 0; i < ARRAY_SIZE(backup_addresses); i++) + ivch_read(dvo, backup_addresses[i], priv->reg_backup + i); + + ivch_dump_regs(dvo); + return true; out: @@ -294,12 +321,31 @@ static enum drm_mode_status ivch_mode_valid(struct intel_dvo_device *dvo, return MODE_OK; } +/* Restore the DVO registers after a resume + * from RAM. Registers have been saved during + * the initialization. + */ +static void ivch_reset(struct intel_dvo_device *dvo) +{ + struct ivch_priv *priv = dvo->dev_priv; + int i; + + DRM_DEBUG_KMS("Resetting the IVCH registers\n"); + + ivch_write(dvo, VR10, 0x0000); + + for (i = 0; i < ARRAY_SIZE(backup_addresses); i++) + ivch_write(dvo, backup_addresses[i], priv->reg_backup[i]); +} + /** Sets the power state of the panel connected to the ivch */ static void ivch_dpms(struct intel_dvo_device *dvo, bool enable) { int i; uint16_t vr01, vr30, backlight; + ivch_reset(dvo); + /* Set the new power state of the panel. */ if (!ivch_read(dvo, VR01, &vr01)) return; @@ -308,6 +354,7 @@ static void ivch_dpms(struct intel_dvo_device *dvo, bool enable) backlight = 1; else backlight = 0; + ivch_write(dvo, VR80, backlight); if (enable) @@ -334,6 +381,8 @@ static bool ivch_get_hw_state(struct intel_dvo_device *dvo) { uint16_t vr01; + ivch_reset(dvo); + /* Set the new power state of the panel. */ if (!ivch_read(dvo, VR01, &vr01)) return false; @@ -348,11 +397,15 @@ static void ivch_mode_set(struct intel_dvo_device *dvo, struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode) { + struct ivch_priv *priv = dvo->dev_priv; uint16_t vr40 = 0; uint16_t vr01 = 0; uint16_t vr10; - ivch_read(dvo, VR10, &vr10); + ivch_reset(dvo); + + vr10 = priv->reg_backup[ARRAY_SIZE(backup_addresses) - 1]; + /* Enable dithering for 18 bpp pipelines */ vr10 &= VR10_INTERFACE_DEPTH_MASK; if (vr10 == VR10_INTERFACE_2X18 || vr10 == VR10_INTERFACE_1X18) @@ -366,7 +419,7 @@ static void ivch_mode_set(struct intel_dvo_device *dvo, uint16_t x_ratio, y_ratio; vr01 |= VR01_PANEL_FIT_ENABLE; - vr40 |= VR40_CLOCK_GATING_ENABLE | VR40_ENHANCED_PANEL_FITTING; + vr40 |= VR40_CLOCK_GATING_ENABLE; x_ratio = (((mode->hdisplay - 1) << 16) / (adjusted_mode->hdisplay - 1)) >> 2; y_ratio = (((mode->vdisplay - 1) << 16) / @@ -381,8 +434,6 @@ static void ivch_mode_set(struct intel_dvo_device *dvo, ivch_write(dvo, VR01, vr01); ivch_write(dvo, VR40, vr40); - - ivch_dump_regs(dvo); } static void ivch_dump_regs(struct intel_dvo_device *dvo) -- 2.30.2