/* SMB handling routines for AMD8111, by YRS 2003.04.
Information on how to access SMBus is provided
by "Alex van Kaam", MANY THANKS!!
Common to AMD8111 and NVidia nForce2
SMBus IO method:
smb_base : Base Address
addr : Slave Device Address
cmd : Command Register
The following note does not apply to NVidia nForce2!
Uses always the lowest bit 1, and read/write is distinguished
by the control command number.
------------------------------------------------------------------------
Note that SMBus Slave Device Address is totall 1byte data,
whose upper 7bits is for address and the lowest bit for read (=1)
and for write (=0).
The input "addr" in the following routines is this 1byte data,
where the lowest bit can be either 0 or 1.
7 0
+-+-+-+-+-+-+-+-+
| Slave addr. |f| f = 0 for write, =1 for read.
+-+-+-+-+-+-+-+-+
Do not confuse "Slave address" which is "addr(here)"/2!
------------------------------------------------------------------------
*/
#ifdef SMB_DEBUG
extern int debug_flag;
#include <stdio.h>
#endif
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include "smbuses.h"
#include "io_cpu.h"
#define LOOP_COUNT 0x2000
#define LOOP_WAIT 0x20
/* command address */
#define SMBGLENB 0x0 /* SMBus global enable */
#define SMBGLSTS 0x1 /* SMBus global status */
#define SMBHADDR 0x2 /* host address register */
#define SMBHCMD 0x3 /* command register for host controller */
#define SMBHDATA0 0x4 /* data 0 register for host controller */
#define SMBHDATA1 0x5 /* data 1 register for host controller */
/* status flag */
#define SMBHSTS_OKOK 0x00 /* transaction successful */
#define SMBHSTS_NOACK 0x10 /* not acknowledged (no device) */
#define SMBHSTS_DEVERR 0x11 /* device error */
#define SMBHSTS_TIMEOUT 0x18 /* timeout */
#define SMBHSTS_PROTERR 0x19 /* protocol error */
#define SMBHSTS_BUSY 0x1A /* device busy or arbitration lost */
#define SMBHSTS_PECERR 0x1F /* PEC(Packet Error Checking) error */
#define SMBHSTS_ALLERR 0x1F /* all bits of error above */
#define SMBHSTS_ALRM 0x40 /* alarm message received */
#define SMBHSTS_DONE 0x80 /* command completed */
/* control command number */
#define SMBHCTRL_BYTEW 0x06 /* write byte */
#define SMBHCTRL_BYTER 0x07 /* read byte */
#define SMBHCTRL_WORDW 0x08 /* write word */
#define SMBHCTRL_WORDR 0x09 /* read word */
static int readbyte(int smb_base, int addr, int cmd)
{
u_char dat = 0, saddr = 2*(addr/2) + 1;
int i;
top:
OUTb((u_short) (smb_base + SMBHADDR), (u_char) saddr); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBHCMD), (u_char) cmd); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBGLENB), SMBHCTRL_BYTER); WAIT; WAIT;
for (i = 0; i < LOOP_WAIT; ++i)
WAIT;
for (i = 0; i < LOOP_COUNT; ++i) {
dat = INb((u_short) (smb_base + SMBGLSTS)); WAIT; WAIT;
#ifdef SMB_DEBUG
fprintf(stderr, " Readbyte: flag = 0x%02X, loop#:%04d\n", dat, i);
#endif
if (dat == SMBHSTS_BUSY || dat == SMBHSTS_TIMEOUT)
goto top;
if (dat & (SMBHSTS_DONE | SMBHSTS_ALLERR))
break;
}
#ifdef SMB_DEBUG
if(i != LOOP_COUNT)
fprintf(stderr,
" fx:Readbyte: addr=0x%02X, cmd=0x%02X flag = 0x%02X, loop#:%04d\n",
addr, cmd, dat, i);
#endif
if (dat == SMBHSTS_DONE) {
dat = INb((u_short) (smb_base + SMBHDATA0)); WAIT; WAIT;
#ifdef SMB_DEBUG
fprintf(stderr, " fy:Readbyte: addr=0x%02X, cmd=0x%02X, dat = 0x%02X\n",
addr, cmd, dat);
#endif
return (dat & 0xFF);
} else
return -1;
}
static int readword(int smb_base, int addr, int cmd)
{
u_char dat = 0, saddr = 2*(addr/2) + 1;
int i;
top:
OUTb((u_short) (smb_base + SMBHADDR), (u_char) saddr); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBHCMD), (u_char) cmd); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBGLENB), SMBHCTRL_WORDR); WAIT; WAIT;
for (i = 0; i < LOOP_WAIT; ++i)
WAIT;
for (i = 0; i < LOOP_COUNT; ++i) {
dat = INb((u_short) (smb_base + SMBGLSTS)); WAIT; WAIT;
if (dat == SMBHSTS_BUSY || dat == SMBHSTS_TIMEOUT)
goto top;
if (dat & (SMBHSTS_DONE | SMBHSTS_ALLERR))
break;
}
#ifdef SMB_DEBUG
if(i != LOOP_COUNT)
fprintf(stderr,
" fx:Readword: addr=0x%02X, cmd=0x%02X flag = 0x%02X, loop#:%04d\n",
addr, cmd, dat, i);
#endif
if (dat == SMBHSTS_DONE) {
i = INb((u_short) (smb_base + SMBHDATA1)); WAIT; WAIT;
dat = INb((u_short) (smb_base + SMBHDATA0)); WAIT; WAIT;
#ifdef SMB_DEBUG
fprintf(stderr, " fy:Readword: addr=0x%02X, cmd=0x%02X, dat = 0x%02X\n",
addr, cmd, dat);
#endif
return (((i << 8) + dat) & 0xFFFF);
} else
return -1;
}
static int writebyte(int smb_base, int addr, int cmd, int value)
{
u_char dat = 0, saddr = 2*(addr/2) + 1;
int i;
top:
OUTb((u_short) (smb_base + SMBHADDR), (u_char) saddr); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBHCMD), (u_char) cmd); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBHDATA0), (u_char) value); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBGLENB), SMBHCTRL_BYTEW); WAIT; WAIT;
for (i = 0; i < LOOP_WAIT; ++i)
WAIT;
for (i = 0; i < LOOP_COUNT; ++i) {
dat = INb((u_short) (smb_base + SMBGLSTS)); WAIT; WAIT;
#ifdef SMB_DEBUG
fprintf(stderr, " Writebyte: flag = 0x%02X, loop#:%04d\n", dat, i);
#endif
if (dat == SMBHSTS_BUSY || dat == SMBHSTS_TIMEOUT)
goto top;
if (dat & (SMBHSTS_DONE | SMBHSTS_ALLERR))
break;
}
#ifdef SMB_DEBUG
if(i != LOOP_COUNT)
fprintf(stderr,
" fx:Writebyte: addr=0x%02X, cmd=0x%02X flag = 0x%02X, loop#:%04d\n",
addr, cmd, dat, i);
#endif
if (dat == SMBHSTS_DONE)
return 0;
else
return -1;
}
static int writeword(int smb_base, int addr, int cmd, int value)
{
u_char dat = 0, saddr = 2*(addr/2) + 1;
int i;
top:
OUTb((u_short) (smb_base + SMBHADDR), (u_char) saddr); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBHCMD), (u_char) cmd); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBHDATA0), (u_char) (value & 0xFF)); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBHDATA1), (u_char) (value >> 8)); WAIT; WAIT;
OUTb((u_short) (smb_base + SMBGLENB), SMBHCTRL_WORDW); WAIT; WAIT;
for (i = 0; i < LOOP_WAIT; ++i)
WAIT;
for (i = 0; i < LOOP_COUNT; ++i) {
dat = INb((u_short) (smb_base + SMBGLSTS)); WAIT; WAIT;
if (dat == SMBHSTS_BUSY || dat == SMBHSTS_TIMEOUT)
goto top;
if (dat & (SMBHSTS_DONE | SMBHSTS_ALLERR))
break;
}
#ifdef SMB_DEBUG
if(i != LOOP_COUNT)
fprintf(stderr,
" fx:Writeword: addr=0x%02X, cmd=0x%02X flag = 0x%02X, loop#:%04d\n",
addr, cmd, dat, i);
#endif
if (dat == SMBHSTS_DONE)
return 0;
else
return -1;
}
struct smbus_io smbus_amd8 = {
readbyte, readword, writebyte, writeword
};
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