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sb/intel/common: SMBus block_cmd_loop()

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For debugging prints, report the number of loop spent
polling instead.

Change-Id: I61865aaafc9f41acd85c5dc98817d12642965ba4
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/21121
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
This commit is contained in:
Kyösti Mälkki
2017-08-20 21:36:24 +03:00
committed by Patrick Georgi
parent c38d543feb
commit 893edeebc6
1 changed files with 79 additions and 97 deletions
Download Patch File Download Diff File Expand all files Collapse all files

176
src/southbridge/intel/common/smbus.c
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@@ -60,6 +60,11 @@
#define SMBUS_TIMEOUT (10 * 1000 * 100) #define SMBUS_TIMEOUT (10 * 1000 * 100)
#define SMBUS_BLOCK_MAXLEN 32 #define SMBUS_BLOCK_MAXLEN 32
/* block_cmd_loop flags */
#define BLOCK_READ 0
#define BLOCK_WRITE (1 << 0)
#define BLOCK_I2C (1 << 1)
static void smbus_delay(void) static void smbus_delay(void)
{ {
inb(0x80); inb(0x80);
@@ -221,13 +226,70 @@ int do_smbus_write_byte(unsigned int smbus_base, u8 device,
return complete_command(smbus_base); return complete_command(smbus_base);
} }
static int block_cmd_loop(unsigned int smbus_base,
u8 *buf, const unsigned int max_bytes, int flags)
{
u8 status;
unsigned int loops = SMBUS_TIMEOUT;
int ret, bytes = 0;
int is_write_cmd = flags & BLOCK_WRITE;
int sw_drives_nak = flags & BLOCK_I2C;
/* Hardware limitations. */
if (flags == (BLOCK_WRITE | BLOCK_I2C))
return SMBUS_ERROR;
/* Poll for transaction completion */
do {
status = inb(smbus_base + SMBHSTSTAT);
if (status & SMBHSTSTS_BYTE_DONE) { /* Byte done */
if (is_write_cmd) {
bytes++;
if (bytes < max_bytes)
outb(*buf++, smbus_base + SMBBLKDAT);
} else {
if (bytes < max_bytes)
*buf++ = inb(smbus_base + SMBBLKDAT);
bytes++;
/* Indicate that next byte is the last one. */
if (sw_drives_nak && (bytes + 1 >= max_bytes)) {
outb(inb(smbus_base + SMBHSTCTL)
| SMBHSTCNT_LAST_BYTE,
smbus_base + SMBHSTCTL);
}
}
/* Engine internally completes the transaction
* and clears HOST_BUSY flag once the byte count
* has been reached or LAST_BYTE was set.
*/
outb(SMBHSTSTS_BYTE_DONE, smbus_base + SMBHSTSTAT);
}
} while (--loops && !host_completed(status));
dprintk("%s: status = %02x, len = %d / %d, loops = %d\n",
__func__, status, bytes, max_bytes, SMBUS_TIMEOUT - loops);
if (loops == 0)
return recover_master(smbus_base,
SMBUS_WAIT_UNTIL_DONE_TIMEOUT);
ret = cb_err_from_stat(status);
if (ret < 0)
return ret;
return bytes;
}
int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd,
unsigned int max_bytes, u8 *buf) unsigned int max_bytes, u8 *buf)
{ {
u8 status;
int ret, slave_bytes; int ret, slave_bytes;
int bytes_read = 0;
unsigned int loops = SMBUS_TIMEOUT;
max_bytes = MIN(SMBUS_BLOCK_MAXLEN, max_bytes); max_bytes = MIN(SMBUS_BLOCK_MAXLEN, max_bytes);
@@ -249,50 +311,22 @@ int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd,
return ret; return ret;
/* Poll for transaction completion */ /* Poll for transaction completion */
do { ret = block_cmd_loop(smbus_base, buf, max_bytes, BLOCK_READ);
status = inb(smbus_base + SMBHSTSTAT);
if (status & SMBHSTSTS_BYTE_DONE) { /* Byte done */
if (bytes_read < max_bytes) {
*buf++ = inb(smbus_base + SMBBLKDAT);
bytes_read++;
}
/* Engine internally completes the transaction
* and clears HOST_BUSY flag once the byte count
* from slave is reached.
*/
outb(SMBHSTSTS_BYTE_DONE, smbus_base + SMBHSTSTAT);
}
} while (--loops && !host_completed(status));
/* Post-check we received complete message. */
slave_bytes = inb(smbus_base + SMBHSTDAT0);
dprintk("%s: status = %02x, len = %d / %d, loops = %d\n",
__func__, status, bytes_read, slave_bytes, loops);
if (loops == 0)
return recover_master(smbus_base,
SMBUS_WAIT_UNTIL_DONE_TIMEOUT);
ret = cb_err_from_stat(status);
if (ret < 0) if (ret < 0)
return ret; return ret;
if (bytes_read < slave_bytes) /* Post-check we received complete message. */
slave_bytes = inb(smbus_base + SMBHSTDAT0);
if (ret < slave_bytes)
return SMBUS_ERROR; return SMBUS_ERROR;
return bytes_read; return ret;
} }
int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd, int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd,
const unsigned int bytes, const u8 *buf) const unsigned int bytes, const u8 *buf)
{ {
u8 status; int ret;
int ret, bytes_sent = 0;
unsigned int loops = SMBUS_TIMEOUT;
if (bytes > SMBUS_BLOCK_MAXLEN) if (bytes > SMBUS_BLOCK_MAXLEN)
return SMBUS_ERROR; return SMBUS_ERROR;
@@ -319,46 +353,21 @@ int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd,
return ret; return ret;
/* Poll for transaction completion */ /* Poll for transaction completion */
do { ret = block_cmd_loop(smbus_base, (u8 *)buf, bytes, BLOCK_WRITE);
status = inb(smbus_base + SMBHSTSTAT);
if (status & SMBHSTSTS_BYTE_DONE) {
bytes_sent++;
if (bytes_sent < bytes)
outb(*buf++, smbus_base + SMBBLKDAT);
/* Engine internally completes the transaction
* and clears HOST_BUSY flag once the byte count
* has been reached.
*/
outb(SMBHSTSTS_BYTE_DONE, smbus_base + SMBHSTSTAT);
}
} while (--loops && !host_completed(status));
dprintk("%s: status = %02x, len = %d / %d, loops = %d\n",
__func__, status, bytes_sent, bytes, loops);
if (loops == 0)
return recover_master(smbus_base,
SMBUS_WAIT_UNTIL_DONE_TIMEOUT);
ret = cb_err_from_stat(status);
if (ret < 0) if (ret < 0)
return ret; return ret;
if (bytes_sent < bytes) if (ret < bytes)
return SMBUS_ERROR; return SMBUS_ERROR;
return bytes_sent; return ret;
} }
/* Only since ICH5 */ /* Only since ICH5 */
int do_i2c_block_read(unsigned int smbus_base, u8 device, int do_i2c_block_read(unsigned int smbus_base, u8 device,
unsigned int offset, const unsigned int bytes, u8 *buf) unsigned int offset, const unsigned int bytes, u8 *buf)
{ {
u8 status; int ret;
int ret, bytes_read = 0;
unsigned int loops = SMBUS_TIMEOUT;
/* Set up for a i2c block data read. /* Set up for a i2c block data read.
* *
@@ -380,40 +389,13 @@ int do_i2c_block_read(unsigned int smbus_base, u8 device,
return ret; return ret;
/* Poll for transaction completion */ /* Poll for transaction completion */
do { ret = block_cmd_loop(smbus_base, buf, bytes, BLOCK_READ | BLOCK_I2C);
status = inb(smbus_base + SMBHSTSTAT);
if (status & SMBHSTSTS_BYTE_DONE) {
if (bytes_read < bytes) {
*buf++ = inb(smbus_base + SMBBLKDAT);
bytes_read++;
}
if (bytes_read + 1 >= bytes) {
/* indicate that next byte is the last one */
outb(inb(smbus_base + SMBHSTCTL)
| SMBHSTCNT_LAST_BYTE,
smbus_base + SMBHSTCTL);
}
outb(SMBHSTSTS_BYTE_DONE, smbus_base + SMBHSTSTAT);
}
} while (--loops && !host_completed(status));
dprintk("%s: status = %02x, len = %d / %d, loops = %d\n",
__func__, status, bytes_read, bytes, loops);
if (loops == 0)
return recover_master(smbus_base,
SMBUS_WAIT_UNTIL_DONE_TIMEOUT);
ret = cb_err_from_stat(status);
if (ret < 0) if (ret < 0)
return ret; return ret;
if (bytes_read < bytes) /* Post-check we received complete message. */
if (ret < bytes)
return SMBUS_ERROR; return SMBUS_ERROR;
return bytes_read; return ret;
} }