psp_smm.c

Go to the documentation of this file.

/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <device/mmio.h>
#include <cpu/x86/msr.h>
#include <cpu/amd/msr.h>
#include <region_file.h>
#include <console/console.h>
#include <amdblocks/psp.h>
#include <soc/iomap.h>
#include <string.h>
 
#include "psp_def.h"
 
#define C2P_BUFFER_MAXSIZE 0xc00 /* Core-to-PSP buffer */
#define P2C_BUFFER_MAXSIZE 0xc00 /* PSP-to-core buffer */
 
struct {
        u8 buffer[C2P_BUFFER_MAXSIZE];
} __attribute__((aligned(32))) c2p_buffer;
 
struct {
        u8 buffer[P2C_BUFFER_MAXSIZE];
} __attribute__((aligned(32))) p2c_buffer;
 
static uint32_t smm_flag; /* Non-zero for SMM, clear when not */
 
static void set_smm_flag(void)
{
        smm_flag = 1;
}
 
static void clear_smm_flag(void)
{
        smm_flag = 0;
}
 
int psp_notify_smm(void)
{
        msr_t msr;
        int cmd_status;
        struct mbox_cmd_smm_info_buffer buffer = {
                .header = {
                        .size = sizeof(buffer)
                },
                .req = {
                        .psp_smm_data_region = (uintptr_t)p2c_buffer.buffer,
                        .psp_smm_data_length = sizeof(p2c_buffer),
                        .psp_mbox_smm_buffer_address = (uintptr_t)c2p_buffer.buffer,
                        .psp_mbox_smm_flag_address = (uintptr_t)&smm_flag,
                }
        };
 
        msr = rdmsr(SMM_ADDR_MSR);
        buffer.req.smm_base = ((uint64_t)msr.hi << 32) | msr.lo;
        msr = rdmsr(SMM_MASK_MSR);
        msr.lo &= 0xffff0000; /* mask SMM_TSEG_VALID and reserved bits */
        buffer.req.smm_mask = ((uint64_t)msr.hi << 32) | msr.lo;
 
        soc_fill_smm_trig_info(&buffer.req.smm_trig_info);
#if (CONFIG(SOC_AMD_COMMON_BLOCK_PSP_GEN2))
        soc_fill_smm_reg_info(&buffer.req.smm_reg_info);
#endif
 
        printk(BIOS_DEBUG, "PSP: Notify SMM info... ");
 
        set_smm_flag();
        cmd_status = send_psp_command(MBOX_BIOS_CMD_SMM_INFO, &buffer);
        clear_smm_flag();
 
        /* buffer's status shouldn't change but report it if it does */
        psp_print_cmd_status(cmd_status, &buffer.header);
 
        return cmd_status;
}
 
/* Notify PSP the system is going to a sleep state. */
void psp_notify_sx_info(u8 sleep_type)
{
        int cmd_status;
        struct mbox_cmd_sx_info_buffer *buffer;
 
        /* PSP verifies that this buffer is at the address specified in psp_notify_smm() */
        buffer = (struct mbox_cmd_sx_info_buffer *)c2p_buffer.buffer;
        memset(buffer, 0, sizeof(*buffer));
        buffer->header.size = sizeof(*buffer);
 
        if (sleep_type > MBOX_BIOS_CMD_SX_INFO_SLEEP_TYPE_MAX) {
                printk(BIOS_ERR, "PSP: BUG: invalid sleep type 0x%x requested\n", sleep_type);
                return;
        }
 
        printk(BIOS_DEBUG, "PSP: Prepare to enter sleep state %d... ", sleep_type);
 
        buffer->sleep_type = sleep_type;
 
        set_smm_flag();
        cmd_status = send_psp_command(MBOX_BIOS_CMD_SX_INFO, buffer);
        clear_smm_flag();
 
        /* buffer's status shouldn't change but report it if it does */
        psp_print_cmd_status(cmd_status, &buffer->header);
}