soc/intel/skl/graphics: Implement panel setup

Logs from Linux' i915 suggest that not even the FSP/GOP takes proper
care of this. The sequence is mostly the same as on older platforms,
with a slightly different configuration of the backlight PWM.

We light the panel up with 50% PWM duty cycle. This often results in
an already rather high perceived brightness, but shouldn't be too
blinding.

Change-Id: I762a77c8df023a4c14af502af5edfeeb961da1ae
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/30246
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
This commit is contained in:
Nico Huber 2018-12-16 02:39:28 +01:00
parent 5d2e1d8023
commit 1a65017a50
2 changed files with 76 additions and 0 deletions

View File

@ -48,6 +48,18 @@ struct soc_intel_skylake_config {
/* Common struct containing soc config data required by common code */
struct soc_intel_common_config common_soc_config;
/* IGD panel configuration */
unsigned int gpu_pp_up_delay_ms;
unsigned int gpu_pp_down_delay_ms;
unsigned int gpu_pp_cycle_delay_ms;
unsigned int gpu_pp_backlight_on_delay_ms;
unsigned int gpu_pp_backlight_off_delay_ms;
unsigned int gpu_pch_backlight_pwm_hz;
enum {
GPU_BACKLIGHT_POLARITY_HIGH = 0,
GPU_BACKLIGHT_POLARITY_LOW,
} gpu_pch_backlight_polarity;
/*
* Interrupt Routing configuration
* If bit7 is 1, the interrupt is disabled.

View File

@ -16,9 +16,11 @@
#include <bootmode.h>
#include <cbmem.h>
#include <commonlib/helpers.h>
#include <console/console.h>
#include <device/pci.h>
#include <device/pci_ops.h>
#include <device/resource.h>
#include <drivers/intel/gma/i915_reg.h>
#include <drivers/intel/gma/libgfxinit.h>
#include <intelblocks/graphics.h>
@ -32,10 +34,72 @@ uintptr_t fsp_soc_get_igd_bar(void)
return graphics_get_memory_base();
}
static void graphics_setup_panel(struct device *dev)
{
struct soc_intel_skylake_config *conf = dev->chip_info;
struct resource *mmio_res;
uint8_t *base;
u32 reg32;
if (!conf)
return;
mmio_res = find_resource(dev, PCI_BASE_ADDRESS_0);
if (!mmio_res || !mmio_res->base)
return;
base = (void *)(uintptr_t)mmio_res->base;
reg32 = conf->gpu_pp_up_delay_ms * 10 << 16;
reg32 |= conf->gpu_pp_backlight_on_delay_ms * 10;
write32(base + PCH_PP_ON_DELAYS, reg32);
reg32 = conf->gpu_pp_down_delay_ms * 10 << 16;
reg32 |= conf->gpu_pp_backlight_off_delay_ms * 10;
write32(base + PCH_PP_OFF_DELAYS, reg32);
reg32 = read32(base + PCH_PP_DIVISOR);
reg32 &= ~0x1f;
reg32 |= (DIV_ROUND_UP(conf->gpu_pp_cycle_delay_ms, 100) + 1) & 0x1f;
write32(base + PCH_PP_DIVISOR, reg32);
/* So far all devices seem to use the PCH PWM function.
The CPU PWM registers are all zero after reset. */
if (conf->gpu_pch_backlight_pwm_hz) {
/* Reference clock is 24MHz. We can choose either a 16
or a 128 step increment. Use 16 if we would have less
than 100 steps otherwise. */
const unsigned int hz_limit = 24 * 1000 * 1000 / 128 / 100;
unsigned int pwm_increment, pwm_period;
u32 south_chicken1;
south_chicken1 = read32(base + SOUTH_CHICKEN1);
if (conf->gpu_pch_backlight_pwm_hz > hz_limit) {
pwm_increment = 16;
south_chicken1 &= ~1;
} else {
pwm_increment = 128;
south_chicken1 |= 1;
}
write32(base + SOUTH_CHICKEN1, south_chicken1);
pwm_period = 24 * 1000 * 1000 / pwm_increment
/ conf->gpu_pch_backlight_pwm_hz;
/* Start with a 50% duty cycle. */
write32(base + BLC_PWM_PCH_CTL2,
pwm_period << 16 | pwm_period / 2);
write32(base + BLC_PWM_PCH_CTL1,
!!conf->gpu_pch_backlight_polarity << 29 |
BLM_PCH_PWM_ENABLE);
}
}
void graphics_soc_init(struct device *dev)
{
u32 ddi_buf_ctl;
graphics_setup_panel(dev);
/*
* Enable DDI-A (eDP) 4-lane operation if the link is not up yet.
* This will allow the kernel to use 4-lane eDP links properly