1 files changed, 58 insertions, 0 deletions
diff --git a/src/soc/amd/stoneyridge/psp.c b/src/soc/amd/stoneyridge/psp.c
new file mode 100644
index 0000000000..bc2d725145
--- /dev/null
+++ b/src/soc/amd/stoneyridge/psp.c
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* This file is part of the coreboot project. */
+
+#include <console/console.h>
+#include <device/pci_ops.h>
+#include <device/pci_def.h>
+#include <cpu/x86/msr.h>
+#include <soc/pci_devs.h>
+#include <soc/northbridge.h>
+#include <soc/southbridge.h>
+#include <amdblocks/psp.h>
+
+void soc_enable_psp_early(void)
+{
+	u32 base, limit, cmd;
+
+	/* Open a posted hole from 0x80000000 : 0xfed00000-1 */
+	base = (0x80000000 >> 8) | MMIO_WE | MMIO_RE;
+	limit = (ALIGN_DOWN(HPET_BASE_ADDRESS - 1, 64 * KiB) >> 8);
+	pci_write_config32(SOC_ADDR_DEV, D18F1_MMIO_LIMIT0_LO, limit);
+	pci_write_config32(SOC_ADDR_DEV, D18F1_MMIO_BASE0_LO, base);
+
+	/* Preload a value into BAR and enable it */
+	pci_write_config32(SOC_PSP_DEV, PSP_MAILBOX_BAR, PSP_MAILBOX_BAR3_BASE);
+	pci_write_config32(SOC_PSP_DEV, PSP_BAR_ENABLES, PSP_MAILBOX_BAR_EN);
+
+	/* Enable memory access and master */
+	cmd = pci_read_config32(SOC_PSP_DEV, PCI_COMMAND);
+	cmd |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
+	pci_write_config32(SOC_PSP_DEV, PCI_COMMAND, cmd);
+};
+
+struct psp_mbox *soc_get_mbox_address(void)
+{
+	uintptr_t psp_mmio;
+
+	/* Check for presence of the PSP */
+	if (pci_read_config32(SOC_PSP_DEV, PCI_VENDOR_ID) == 0xffffffff) {
+		printk(BIOS_WARNING, "PSP: No SOC_PSP_DEV found at D%xF%x\n",
+			PSP_DEV, PSP_FUNC);
+		return 0;
+	}
+
+	/* Determine if Bar3Hide has been set, and if hidden get the base from
+	 * the MSR instead. */
+	if (pci_read_config32(SOC_PSP_DEV, PSP_BAR_ENABLES) & BAR3HIDE) {
+		psp_mmio = rdmsr(MSR_CU_CBBCFG).lo;
+		if (psp_mmio == 0xffffffff) {
+			printk(BIOS_WARNING, "PSP: BAR hidden, MSR val uninitialized\n");
+			return 0;
+		}
+	} else {
+		psp_mmio = pci_read_config32(SOC_PSP_DEV, PCI_BASE_ADDRESS_4) &
+				~PCI_BASE_ADDRESS_MEM_ATTR_MASK;
+	}
+
+	return (struct psp_mbox *)(psp_mmio + PSP_MAILBOX_OFFSET);
+}