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/* SPDX-License-Identifier: GPL-2.0-only */
#include <amdblocks/agesawrapper.h>
#include <amdblocks/acpimmio.h>
#include <console/console.h>
#include <device/pci_def.h>
#include <device/device.h>
#include <device/smbus_host.h>
#include <soc/southbridge.h>
#include <amdblocks/dimm_spd.h>
/*
* readspd - Read one or more SPD bytes from a DIMM.
* Start with offset zero and read sequentially.
* Optimization relies on autoincrement to avoid
* sending offset for every byte.
* Reads 128 bytes in 7-8 ms at 400 KHz.
*/
static int readspd(uint8_t SmbusSlaveAddress, char *buffer, size_t count)
{
uint8_t dev_addr;
size_t index;
int error;
char *pbuf = buffer;
printk(BIOS_SPEW, "-------------READING SPD-----------\n");
printk(BIOS_SPEW, "SmbusSlave: 0x%08X, count: %zd\n",
SmbusSlaveAddress, count);
/*
* Convert received device address to the format accepted by
* do_smbus_read_byte and do_smbus_recv_byte.
*/
dev_addr = (SmbusSlaveAddress >> 1);
/* Read the first SPD byte */
error = do_smbus_read_byte((uintptr_t)acpimmio_smbus, dev_addr, 0);
if (error < 0) {
printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n");
return error;
}
*pbuf = (char)error;
pbuf++;
/* Read the remaining SPD bytes using do_smbus_recv_byte for speed */
for (index = 1 ; index < count ; index++) {
error = do_smbus_recv_byte((uintptr_t)acpimmio_smbus, dev_addr);
if (error < 0) {
printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n");
return error;
}
*pbuf = (char)error;
pbuf++;
}
printk(BIOS_SPEW, "\n");
printk(BIOS_SPEW, "-------------FINISHED READING SPD-----------\n");
return 0;
}
int sb_read_spd(uint8_t spdAddress, char *buf, size_t len)
{
return readspd(spdAddress, buf, len);
}
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