soc/amd/picasso/romstage: Set HDA disable UPD if controller disabled

FSP has recently added support for a UPD switch to disable the non-GPU
HD Audio controller. This change adds the coreboot side of the feature.
To avoid having two HD Audio enable options, the value of the
hd_audio_enable UPD is determined by the enable state of the non-GPU HD
Audio controller in the platform devicetree.

BUG=b:158535201,b:162302028
BRANCH=zork
TEST=With the corresponding FSP change applied the non-GPU HD Audio
device is hidden when switched off in devicetree and remains present and
functional when switched on in devicetree.

Change-Id: Ib2965e0742f4148e42a44ddad8ee05f0c4c7237e
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44680
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Matt Papageorge <matthewpapa07@gmail.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/src/soc/amd/picasso/romstage.c b/src/soc/amd/picasso/romstage.c
index 342fd467ec..0accc49cfa 100644
--- a/src/soc/amd/picasso/romstage.c
+++ b/src/soc/amd/picasso/romstage.c
@@ -9,11 +9,13 @@
 #include <console/uart.h>
 #include <commonlib/helpers.h>
 #include <console/console.h>
+#include <device/device.h>
 #include <program_loading.h>
 #include <elog.h>
 #include <soc/acpi.h>
 #include <soc/memmap.h>
 #include <soc/mrc_cache.h>
+#include <soc/pci_devs.h>
 #include <types.h>
 #include "chip.h"
 #include <fsp/api.h>
@@ -38,6 +40,30 @@ static void add_chipset_state_cbmem(int unused)
 
 ROMSTAGE_CBMEM_INIT_HOOK(add_chipset_state_cbmem);
 
+static const struct device_path hda_path[] = {
+	{
+		.type = DEVICE_PATH_PCI,
+		.pci.devfn = PCIE_GPP_A_DEVFN
+	},
+	{
+		.type = DEVICE_PATH_PCI,
+		.pci.devfn = HD_AUDIO_DEVFN
+	},
+};
+
+static bool devtree_hda_dev_enabled(void)
+{
+	const struct device *hda_dev;
+
+	hda_dev = find_dev_nested_path(pci_root_bus(), hda_path, ARRAY_SIZE(hda_path));
+
+	if (!hda_dev)
+		return false;
+
+	return hda_dev->enabled;
+}
+
+
 void platform_fsp_memory_init_params_cb(FSPM_UPD *mupd, uint32_t version)
 {
 	FSP_M_CONFIG *mcfg = &mupd->FspmConfig;
@@ -88,6 +114,7 @@ void platform_fsp_memory_init_params_cb(FSPM_UPD *mupd, uint32_t version)
 	mcfg->telemetry_vddcr_vdd_offset = config->telemetry_vddcr_vdd_offset;
 	mcfg->telemetry_vddcr_soc_slope = config->telemetry_vddcr_soc_slope;
 	mcfg->telemetry_vddcr_soc_offset = config->telemetry_vddcr_soc_offset;
+	mcfg->hd_audio_enable = devtree_hda_dev_enabled();
 }
 
 asmlinkage void car_stage_entry(void)