[M] Change in coreboot[main]: soc/amd/common/psp_smi_flash: implement SPI read/wrire/erase command

[Felix Held (Code Review)]

Attention is currently required from: Fred Reitberger, Jason Glenesk, Matt DeVillier, ritul guru.

Hello ritul guru,

I'd like you to do a code review.
Please visit

https://review.coreboot.org/c/coreboot/+/83777?usp=email

to review the following change.

Change subject: soc/amd/common/psp_smi_flash: implement SPI read/wrire/erase command
......................................................................

soc/amd/common/psp_smi_flash: implement SPI read/wrire/erase command

Use coreboot's SPI flash access infrastructure to do the flash read,
write, or erase operations as requested from the PSP.

This patch is a modified version of parts of CB:65523.

Document #55758 Rev. 2.04 was used as a reference.

Test=When selecting SOC_AMD_COMMON_BLOCK_PSP_SMI, Mandolin still builds

Signed-off-by: Felix Held 
Signed-off-by: Ritul Guru 
Change-Id: I4957a6d316015cc7037acf52facb6cc69188d446
---
M src/soc/amd/common/block/psp/psp_smi_flash.c
1 file changed, 112 insertions(+), 3 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/77/83777/1

diff --git a/src/soc/amd/common/block/psp/psp_smi_flash.c b/src/soc/amd/common/block/psp/psp_smi_flash.c
index 420fb94..2d075ef 100644
--- a/src/soc/amd/common/block/psp/psp_smi_flash.c
+++ b/src/soc/amd/common/block/psp/psp_smi_flash.c
@@ -85,6 +85,25 @@
    write64(&cmd_buf->req.num_blocks, num_blocks);
 }

+static void get_psp_spi_read_write(struct mbox_pspv2_cmd_spi_read_write *cmd_buf,
+				   u64 *target_nv_id, u64 *lba, u64 *offset,
+				   u64 *num_bytes, u8 **data)
+{
+	*target_nv_id = read64(&cmd_buf->req.target_nv_id);
+	*lba = read64(&cmd_buf->req.lba);
+	*offset = read64(&cmd_buf->req.offset);
+	*num_bytes = read64(&cmd_buf->req.num_bytes);
+	*data = cmd_buf->req.buffer;
+}
+
+static void get_psp_spi_erase(struct mbox_pspv2_cmd_spi_erase *cmd_buf,
+			      u64 *target_nv_id, u64 *lba, u64 *num_blocks)
+{
+	*target_nv_id = read64(&cmd_buf->req.target_nv_id);
+	*lba = read64(&cmd_buf->req.lba);
+	*num_blocks = read64(&cmd_buf->req.num_blocks);
+}
+
 static const char *id_to_region_name(u64 target_nv_id)
 {
    switch (target_nv_id) {
@@ -197,37 +216,127 @@
 {
    struct mbox_pspv2_cmd_spi_read_write *const cmd_buf =
    	(struct mbox_pspv2_cmd_spi_read_write *)buffer;
+	enum mbox_p2c_status ret;
+	u64 target_nv_id;
+	u64 lba;
+	u64 offset;
+	u64 num_bytes;
+	u8 *data;
+	size_t addr;
+	const struct spi_flash *flash;
+	struct region_device store;

printk(BIOS_SPEW, "PSP: SPI read request\n");

if (!is_valid_psp_spi_read_write(cmd_buf))
    	return MBOX_PSP_COMMAND_PROCESS_ERROR;

-	return MBOX_PSP_UNSUPPORTED;
+	if (!spi_controller_available()) {
+		printk(BIOS_NOTICE, "PSP: SPI controller busy\n");
+		return MBOX_PSP_SPI_BUSY;
+	}
+
+	get_psp_spi_read_write(cmd_buf, &target_nv_id, &lba, &offset, &num_bytes, &data);
+
+	ret = find_psp_spi_flash_device_region(target_nv_id, &store, &flash);
+
+	if (ret != MBOX_PSP_SUCCESS)
+		return ret;
+
+	addr = (lba * flash->sector_size) + offset;
+
+	printk(BIOS_SPEW, "PSP: SPI read 0x%llx bytes at 0x%zx\n", num_bytes, addr);
+
+	if (rdev_readat(&store, data, addr, (size_t)num_bytes) != (size_t)num_bytes) {
+		printk(BIOS_ERR, "PSP: Failed to read NVRAM data\n");
+		return MBOX_PSP_COMMAND_PROCESS_ERROR;
+	}
+
+	return MBOX_PSP_SUCCESS;
 }

enum mbox_p2c_status psp_smi_spi_write(struct mbox_default_buffer *buffer)
 {
    struct mbox_pspv2_cmd_spi_read_write *const cmd_buf =
    	(struct mbox_pspv2_cmd_spi_read_write *)buffer;
+	enum mbox_p2c_status ret;
+	u64 target_nv_id;
+	u64 lba;
+	u64 offset;
+	u64 num_bytes;
+	u8 *data;
+	size_t addr;
+	const struct spi_flash *flash;
+	struct region_device store;

printk(BIOS_SPEW, "PSP: SPI write request\n");

if (!is_valid_psp_spi_read_write(cmd_buf))
    	return MBOX_PSP_COMMAND_PROCESS_ERROR;

-	return MBOX_PSP_UNSUPPORTED;
+	if (!spi_controller_available()) {
+		printk(BIOS_NOTICE, "PSP: SPI controller busy\n");
+		return MBOX_PSP_SPI_BUSY;
+	}
+
+	get_psp_spi_read_write(cmd_buf, &target_nv_id, &lba, &offset, &num_bytes, &data);
+
+	ret = find_psp_spi_flash_device_region(target_nv_id, &store, &flash);
+
+	if (ret != MBOX_PSP_SUCCESS)
+		return ret;
+
+	addr = (lba * flash->sector_size) + offset;
+
+	printk(BIOS_SPEW, "PSP: SPI write 0x%llx bytes at 0x%zx\n", num_bytes, addr);
+
+	if (rdev_writeat(&store, data, addr, (size_t)num_bytes) != (size_t)num_bytes) {
+		printk(BIOS_ERR, "PSP: Failed to write NVRAM data\n");
+		return MBOX_PSP_COMMAND_PROCESS_ERROR;
+	}
+
+	return MBOX_PSP_SUCCESS;
 }

enum mbox_p2c_status psp_smi_spi_erase(struct mbox_default_buffer *buffer)
 {
    struct mbox_pspv2_cmd_spi_erase *const cmd_buf =
    	(struct mbox_pspv2_cmd_spi_erase *)buffer;
+	enum mbox_p2c_status ret;
+	u64 target_nv_id;
+	u64 lba;
+	u64 num_blocks;
+	size_t addr;
+	size_t num_bytes;
+	const struct spi_flash *flash;
+	struct region_device store;

printk(BIOS_SPEW, "PSP: SPI erase request\n");

if (!is_valid_psp_spi_erase(cmd_buf))
    	return MBOX_PSP_COMMAND_PROCESS_ERROR;

-	return MBOX_PSP_UNSUPPORTED;
+	if (!spi_controller_available()) {
+		printk(BIOS_NOTICE, "PSP: SPI controller busy\n");
+		return MBOX_PSP_SPI_BUSY;
+	}
+
+	get_psp_spi_erase(cmd_buf, &target_nv_id, &lba, &num_blocks);
+
+	ret = find_psp_spi_flash_device_region(target_nv_id, &store, &flash);
+
+	if (ret != MBOX_PSP_SUCCESS)
+		return ret;
+
+	addr = lba * flash->sector_size;
+	num_bytes = (size_t)num_blocks * flash->sector_size;
+
+	printk(BIOS_SPEW, "PSP: SPI erase 0x%zx bytes at 0x%zx\n", num_bytes, addr);
+
+	if (rdev_eraseat(&store, addr, num_bytes) != num_bytes) {
+		printk(BIOS_ERR, "PSP: Failed to erase SPI NVRAM data\n");
+		return MBOX_PSP_COMMAND_PROCESS_ERROR;
+	}
+
+	return MBOX_PSP_SUCCESS;
 }