soc/amd/stoneyridge: Replace magic registers

Replace southbridge registers and register values from magic numbers to
literals, provided these registers are currently defined publicly or in
NDA datasheet.

Registers available only internally to AMD are left unchanged.

BUG=b:62199625

Change-Id: I9187ba1c41ebb1201ddc177e8184672c60cd5f5d
Signed-off-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Reviewed-on: https://review.coreboot.org/21767
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>

1 files changed, 27 insertions, 28 deletions

diff --git a/src/soc/amd/stoneyridge/smbus_spd.c b/src/soc/amd/stoneyridge/smbus_spd.c
index 9bbce5bc25..605f8da78e 100644
--- a/src/soc/amd/stoneyridge/smbus_spd.c
+++ b/src/soc/amd/stoneyridge/smbus_spd.c
@@ -20,10 +20,10 @@
 #include <Porting.h>
 #include <AGESA.h>
 #include <soc/southbridge.h>
+#include <soc/smbus.h>
 #include <dimmSpd.h>
 
-/*-----------------------------------------------------------------------------
- *
+/*
  * readSmbusByteData - read a single SPD byte from any offset
  */
 static int readSmbusByteData(int iobase, int address, char *buffer, int offset)
@@ -33,33 +33,32 @@ static int readSmbusByteData(int iobase, int address, char *buffer, int offset)
 
 	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
+	__outbyte(iobase + SMBHSTSTAT, SMBHST_STAT_CLEAR);
+	__outbyte(iobase + SMBSLVSTAT, SMBSLV_STAT_CLEAR);
+	__outbyte(iobase + SMBHSTCMD, offset);		// offset in eeprom
+	__outbyte(iobase + SMBHSTADDR, address);	// slave addr & read bit
+	__outbyte(iobase + SMBHSTCTRL, SMBHST_CTRL_STRT + SMBHST_CTRL_BDT_RW);
 
 	// time limit to avoid hanging for unexpected error status
 	limit = __rdtsc() + 2000000000 / 10;
 	for (;;) {
-		status = __inbyte(iobase);
+		status = __inbyte(iobase + SMBHSTSTAT);
 		if (__rdtsc() > limit)
 			break;
-		if ((status & 2) == 0)
+		if ((status & SMBHST_STAT_INTERRUPT) == 0)
 			continue;	// SMBusInterrupt not set, keep waiting
-		if ((status & 1) == 1)
+		if ((status & SMBHST_STAT_BUSY) == SMBHST_STAT_BUSY)
 			continue;	// HostBusy set, keep waiting
 		break;
 	}
 
-	buffer[0] = __inbyte(iobase + 5);
-	if (status == 2)
-		status = 0;		// check for done with no errors
+	buffer[0] = __inbyte(iobase + SMBHSTDAT0);
+	if (status == SMBHST_STAT_NOERROR)
+		status = 0;		// done with no errors
 	return status;
 }
 
-/*-----------------------------------------------------------------------------
- *
+/*
  * readSmbusByte - read a single SPD byte from the default offset
  *                 this function is faster function readSmbusByteData
  */
@@ -68,30 +67,29 @@ 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
+	__outbyte(iobase + SMBHSTSTAT, SMBHST_STAT_CLEAR);
+	__outbyte(iobase + SMBHSTCTRL, SMBHST_CTRL_STRT + SMBHST_CTRL_BTE_RW);
 
 	// time limit to avoid hanging for unexpected error status
 	limit = __rdtsc() + 2000000000 / 10;
 	for (;;) {
-		status = __inbyte(iobase);
+		status = __inbyte(iobase + SMBHSTSTAT);
 		if (__rdtsc() > limit)
 			break;
-		if ((status & 2) == 0)
+		if ((status & SMBHST_STAT_INTERRUPT) == 0)
 			continue;	// SMBusInterrupt not set, keep waiting
-		if ((status & 1) == 1)
+		if ((status & SMBHST_STAT_BUSY) == SMBHST_STAT_BUSY)
 			continue;	// HostBusy set, keep waiting
 		break;
 	}
 
-	buffer[0] = __inbyte(iobase + 5);
-	if (status == 2)
-		status = 0;		// check for done with no errors
+	buffer[0] = __inbyte(iobase + SMBHSTDAT0);
+	if (status == SMBHST_STAT_NOERROR)
+		status = 0;		// 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
@@ -115,7 +113,7 @@ static int readspd(int iobase, int SmbusSlaveAddress, char *buffer, int count)
 	}
 
 	/* read the remaining bytes using auto-increment for speed */
-	for (index = 1 ; index < count ; index++) {
+	for (index = 1; index < count; index++) {
 		error = readSmbusByte(iobase, SmbusSlaveAddress,
 					&buffer[index]);
 		if (error) {
@@ -137,15 +135,16 @@ static void writePmReg(int reg, int data)
 
 static void setupFch(int ioBase)
 {
+	/* register 0x2c and 0x2d are not defined in public datasheet */
 	writePmReg(0x2d, ioBase >> 8);
 	writePmReg(0x2c, ioBase | 1);
 	/* set SMBus clock to 400 KHz */
-	__outbyte(ioBase + 0x0e, 66000000 / 400000 / 4);
+	__outbyte(ioBase + SMBTIMING, 66000000 / 400000 / 4);
 }
 
 int sb_readSpd(int spdAddress, char *buf, size_t len)
 {
-	int ioBase = 0xb00;
+	int ioBase = SMB_BASE_ADDR;
 	setupFch(ioBase);
 	return readspd(ioBase, spdAddress, buf, len);
 }