diff options
| author | Andrew Chew <achew@nvidia.com> | 2014-02-10 16:44:18 -0800 |
|---|---|---|
| committer | Marc Jones <marc.jones@se-eng.com> | 2014-11-12 20:16:43 +0100 |
| commit | 7f0cb159994985dffe76ff034aae5a844386b447 (patch) | |
| tree | baa2a38b2b123df06562340ff643191ab771e2bc /src/soc | |
| parent | 372a5bbd66cb247abed173685d4a6fe0a3188246 (diff) | |
tegra124: Program PWM1 to drive panel backlight
Repurpose config->pwm to mean the particular PWM device (we use PWM1 on
nyan), and add code to program the PWM device.
BUG=none
TEST=emerge-nyan chromeos-coreboot-nyan, regenerate bootimage, and boot.
See that the backlight comes up in the bootloader, and brightness can be
adjusted via pwm_bl driver in the kernel.
Original-Change-Id: I2db047e5ef23c0e8fb66dd05ad6339d60918d493
Original-Signed-off-by: Andrew Chew <achew@nvidia.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/185772
Original-Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
(cherry picked from commit 0dee98dd0c8510ecd630b5c6cb9ea49724dc8b55)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Change-Id: Ie53610f3afa30b2d8f484685fb0e8c0b12cd8241
Reviewed-on: http://review.coreboot.org/7402
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Diffstat (limited to 'src/soc')
| -rw-r--r-- | src/soc/nvidia/tegra124/display.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/src/soc/nvidia/tegra124/display.c b/src/soc/nvidia/tegra124/display.c index 2fbec50cf8..8c4e8232dd 100644 --- a/src/soc/nvidia/tegra124/display.c +++ b/src/soc/nvidia/tegra124/display.c @@ -33,6 +33,7 @@ #include <edid.h> #include <soc/clock.h> #include <soc/nvidia/tegra/dc.h> +#include <soc/nvidia/tegra/pwm.h> #include <soc/nvidia/tegra124/sdram.h> #include "chip.h" #include <soc/display.h> @@ -240,6 +241,7 @@ void display_startup(device_t dev) int i; struct soc_nvidia_tegra124_config *config = dev->chip_info; struct display_controller *dc = (void *)config->display_controller; + struct pwm_controller *pwm = (void *)TEGRA_PWM_BASE; struct disp_ctl_win window; /* should probably just make it all MiB ... in future */ @@ -270,11 +272,15 @@ void display_startup(device_t dev) __func__, config->backlight_en_gpio, 1); } - if (config->pwm){ - gpio_output(config->pwm, 1); - printk(BIOS_SPEW,"%s: pwm setting gpio %08x to %d\n", - __func__, config->pwm, 1); - } + /* Set up Tegra PWM n (where n is specified in config->pwm) to drive the + * panel backlight. + */ + printk(BIOS_SPEW, "%s: enable panel backlight pwm\n", __func__); + WRITEL(((1 << NV_PWM_CSR_ENABLE_SHIFT) | + (220 << NV_PWM_CSR_PULSE_WIDTH_SHIFT) | /* 220/256 */ + 0x02e), /* frequency divider */ + &pwm->pwm[config->pwm].csr); + printk(BIOS_SPEW, "%s: xres %d yres %d framebuffer_bits_per_pixel %d\n", __func__, |