i2c: piix4: Fix probing of reserved ports on AMD Family 16h Model 30h

Prevent bus timeouts and resets on Family 16h Model 30h by not probing
reserved Ports 3 and 4.

According to the AMD BIOS and Kernel Developer's Guides (BKDG), Port 3
and Port 4 are reserved on the following devices:
 - Family 15h Model 60h-6Fh
 - Family 15h Model 70h-7Fh
 - Family 16h Model 30h-3Fh

Based on earlier work by Andrew Cooks.

Reported-by: Andrew Cooks <andrew.cooks@opengear.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Jean Delvare 2019-08-02 14:54:38 +02:00 committed by Wolfram Sang
parent ba91940356
commit 528d53a159

View file

@ -72,7 +72,8 @@
#define PIIX4_BLOCK_DATA 0x14
/* Multi-port constants */
#define PIIX4_MAX_ADAPTERS 4
#define PIIX4_MAX_ADAPTERS 4
#define HUDSON2_MAIN_PORTS 2 /* HUDSON2, KERNCZ reserves ports 3, 4 */
/* SB800 constants */
#define SB800_PIIX4_SMB_IDX 0xcd6
@ -808,6 +809,7 @@ MODULE_DEVICE_TABLE (pci, piix4_ids);
static struct i2c_adapter *piix4_main_adapters[PIIX4_MAX_ADAPTERS];
static struct i2c_adapter *piix4_aux_adapter;
static int piix4_adapter_count;
static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
bool sb800_main, u8 port, bool notify_imc,
@ -867,7 +869,15 @@ static int piix4_add_adapters_sb800(struct pci_dev *dev, unsigned short smba,
int port;
int retval;
for (port = 0; port < PIIX4_MAX_ADAPTERS; port++) {
if (dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS ||
(dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS &&
dev->revision >= 0x1F)) {
piix4_adapter_count = HUDSON2_MAIN_PORTS;
} else {
piix4_adapter_count = PIIX4_MAX_ADAPTERS;
}
for (port = 0; port < piix4_adapter_count; port++) {
retval = piix4_add_adapter(dev, smba, true, port, notify_imc,
piix4_main_port_names_sb800[port],
&piix4_main_adapters[port]);
@ -989,7 +999,7 @@ static void piix4_adap_remove(struct i2c_adapter *adap)
static void piix4_remove(struct pci_dev *dev)
{
int port = PIIX4_MAX_ADAPTERS;
int port = piix4_adapter_count;
while (--port >= 0) {
if (piix4_main_adapters[port]) {