hwmon: (k10temp) Do not blacklist known working CPU models

When detecting AM2+ or AM3 socket with DDR2, only blacklist cores which are known to exist in AM2+ format. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Clemens Ladisch <clemens@ladisch.de> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: stable@kernel.org

hwmon: (k10temp) Do not blacklist known working CPU models
When detecting AM2+ or AM3 socket with DDR2, only blacklist cores which are known to exist in AM2+ format. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Clemens Ladisch <clemens@ladisch.de> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: stable@kernel.org
Jean Delvare
1 parent 7e27d6e778
Showing 1 changed file with 12 additions and 2 deletions Side-by-side Diff
drivers/hwmon/k10temp.c
@@ -112,11 +112,21 @@
 	if (pkg_type != CPUID_PKGTYPE_AM2R2_AM3)
 		return false;
  
-	/* Differentiate between AM2+ (bad) and AM3 (good) */
+	/* DDR3 memory implies socket AM3, which is good */
 	pci_bus_read_config_dword(pdev->bus,
 				  PCI_DEVFN(PCI_SLOT(pdev->devfn), 2),
 				  REG_DCT0_CONFIG_HIGH, &reg_dram_cfg);
-	return !(reg_dram_cfg & DDR3_MODE);
+	if (reg_dram_cfg & DDR3_MODE)
+		return false;
+
+	/*
+	 * Unfortunately it is possible to run a socket AM3 CPU with DDR2
+	 * memory. We blacklist all the cores which do exist in socket AM2+
+	 * format. It still isn't perfect, as RB-C2 cores exist in both AM2+
+	 * and AM3 formats, but that's the best we can do.
+	 */
+	return boot_cpu_data.x86_model < 4 ||
+	       (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask <= 2);
 }
  
 static int __devinit k10temp_probe(struct pci_dev *pdev,
...	...	@@ -112,11 +112,21 @@
112	112	if (pkg_type != CPUID_PKGTYPE_AM2R2_AM3)
113	113	return false;
114	114
115		- /* Differentiate between AM2+ (bad) and AM3 (good) */
	115	+ /* DDR3 memory implies socket AM3, which is good */
116	116	pci_bus_read_config_dword(pdev->bus,
117	117	PCI_DEVFN(PCI_SLOT(pdev->devfn), 2),
118	118	REG_DCT0_CONFIG_HIGH, &reg_dram_cfg);
119		- return !(reg_dram_cfg & DDR3_MODE);
	119	+ if (reg_dram_cfg & DDR3_MODE)
	120	+ return false;
	121	+
	122	+ /*
	123	+ * Unfortunately it is possible to run a socket AM3 CPU with DDR2
	124	+ * memory. We blacklist all the cores which do exist in socket AM2+
	125	+ * format. It still isn't perfect, as RB-C2 cores exist in both AM2+
	126	+ * and AM3 formats, but that's the best we can do.
	127	+ */
	128	+ return boot_cpu_data.x86_model < 4 \|\|
	129	+ (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask <= 2);
120	130	}
121	131
122	132	static int __devinit k10temp_probe(struct pci_dev *pdev,