From 528d53a1592b0e27c423f7cafc1df85f77fc1163 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Fri, 2 Aug 2019 14:54:38 +0200 Subject: [PATCH] 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 Signed-off-by: Jean Delvare Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-piix4.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c index c46c4bddc7ca3..d9f7e771f6ad7 100644 --- a/drivers/i2c/busses/i2c-piix4.c +++ b/drivers/i2c/busses/i2c-piix4.c @@ -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]) {