| /* SPDX-License-Identifier: GPL-2.0-only */ |
| |
| #include <amdblocks/acpimmio.h> |
| #include <console/console.h> |
| #include <device/pci_def.h> |
| #include <device/device.h> |
| |
| /* warning: Porting.h includes an open #pragma pack(1) */ |
| #include <Porting.h> |
| #include <AGESA.h> |
| #include <amdlib.h> |
| #include <northbridge/amd/pi/dimmSpd.h> |
| |
| /*----------------------------------------------------------------------------- |
| * |
| * readSmbusByteData - read a single SPD byte from any offset |
| */ |
| |
| static int readSmbusByteData(int iobase, int address, char *buffer, int offset) |
| { |
| unsigned int status; |
| UINT64 limit; |
| |
| address |= 1; // set read bit |
| |
| __outbyte(iobase + 0, 0xFF); // clear error status |
| __outbyte(iobase + 1, 0x1F); // clear error status |
| __outbyte(iobase + 3, offset); // offset in eeprom |
| __outbyte(iobase + 4, address); // slave address and read bit |
| __outbyte(iobase + 2, 0x48); // read byte command |
| |
| // time limit to avoid hanging for unexpected error status (should never happen) |
| limit = __rdtsc() + 2000000000 / 10; |
| for (;;) |
| { |
| status = __inbyte(iobase); |
| if (__rdtsc() > limit) break; |
| if ((status & 2) == 0) continue; // SMBusInterrupt not set, keep waiting |
| if ((status & 1) == 1) continue; // HostBusy set, keep waiting |
| break; |
| } |
| |
| buffer [0] = __inbyte(iobase + 5); |
| if (status == 2) status = 0; // check for done with no errors |
| return status; |
| } |
| |
| /*----------------------------------------------------------------------------- |
| * |
| * readSmbusByte - read a single SPD byte from the default offset |
| * this function is faster function readSmbusByteData |
| */ |
| |
| static int readSmbusByte(int iobase, int address, char *buffer) |
| { |
| unsigned int status; |
| UINT64 limit; |
| |
| __outbyte(iobase + 0, 0xFF); // clear error status |
| __outbyte(iobase + 2, 0x44); // read command |
| |
| // time limit to avoid hanging for unexpected error status |
| limit = __rdtsc() + 2000000000 / 10; |
| for (;;) |
| { |
| status = __inbyte(iobase); |
| if (__rdtsc() > limit) break; |
| if ((status & 2) == 0) continue; // SMBusInterrupt not set, keep waiting |
| if ((status & 1) == 1) continue; // HostBusy set, keep waiting |
| break; |
| } |
| |
| buffer [0] = __inbyte(iobase + 5); |
| if (status == 2) status = 0; // check for done with no errors |
| return status; |
| } |
| |
| /*--------------------------------------------------------------------------- |
| * |
| * 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(int iobase, int SmbusSlaveAddress, char *buffer, int count) |
| { |
| int index, error; |
| |
| printk(BIOS_SPEW, "-------------READING SPD-----------\n"); |
| printk(BIOS_SPEW, "iobase: 0x%08X, SmbusSlave: 0x%08X, count: %d\n", |
| iobase, SmbusSlaveAddress, count); |
| |
| /* read the first byte using offset zero */ |
| error = readSmbusByteData(iobase, SmbusSlaveAddress, buffer, 0); |
| |
| if (error) { |
| printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n"); |
| return error; |
| } |
| |
| /* read the remaining bytes using auto-increment for speed */ |
| for (index = 1; index < count; index++) |
| { |
| error = readSmbusByte(iobase, SmbusSlaveAddress, &buffer [index]); |
| if (error) { |
| printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n"); |
| return error; |
| } |
| } |
| printk(BIOS_SPEW, "\n"); |
| printk(BIOS_SPEW, "-------------FINISHED READING SPD-----------\n"); |
| |
| return 0; |
| } |
| |
| static void setupFch(int ioBase) |
| { |
| pm_write16(0x2c, ioBase | 1); |
| __outbyte(ioBase + 0x0E, 66000000 / 400000 / 4); // set SMBus clock to 400 KHz |
| } |
| |
| int hudson_readSpd(int spdAddress, char *buf, size_t len) |
| { |
| int ioBase = 0xB00; |
| setupFch(ioBase); |
| return readspd(ioBase, spdAddress, buf, len); |
| } |