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Subject[PATCH][retry 4] Conform L3 Cache Index Disable to Linux standards
Date

Add ABI Documentation entry and fix some /sys directory formating
issues with the L3 Cache Index Disable feature for future AMD
processors. Add a check to disable it for family 0x10 models
that do not support it yet.

Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>

diff --git a/Documentation/ABI/testing/sysfs-devices-cache_disable b/Documentation/ABI/testing/sysfs-devices-cache_disable
new file mode 100644
index 0000000..c7d9174
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-cache_disable
@@ -0,0 +1,18 @@
+What: /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
+Date: August 2008
+KernelVersion: 2.6.27
+Contact: mark.langsdorf@amd.com
+Description: These files exist in every cpu's cache index directories.
+ There are currently 2 cache_disable_# files in each
+ directory. Reading from these files on a supported
+ processor will return that cache disable index value
+ for that processor and node. Writing to one of these
+ files will cause the specificed cache index to be disabled.
+
+ Currently, only AMD Family 10h Processors support cache index
+ disable, and only for their L3 caches. See the BIOS and
+ Kernel Developer's Guide at
+ http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116-Public-GH-BKDG_3.20_2-4-09.pdf
+ for formatting information and other details on the
+ cache index disable.
+Users: joachim.deguara@amd.com
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 72c65bc..2547807 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -81,7 +81,7 @@ obj-$(CONFIG_EARLY_PRINTK) += early_printk.o

obj-$(CONFIG_HPET_TIMER) += hpet.o

-obj-$(CONFIG_K8_NB) += k8.o
+obj-y += k8.o
obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o
obj-$(CONFIG_DEBUG_RODATA_TEST) += test_rodata.o
obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o
diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index 8e6ce2c..5ecac89 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -18,6 +18,9 @@
#include <asm/processor.h>
#include <asm/smp.h>

+#include <linux/pci.h>
+#include <asm/k8.h>
+
#define LVL_1_INST 1
#define LVL_1_DATA 2
#define LVL_2 3
@@ -159,14 +162,6 @@ struct _cpuid4_info_regs {
unsigned long can_disable;
};

-#if defined(CONFIG_PCI) && defined(CONFIG_SYSFS)
-static struct pci_device_id k8_nb_id[] = {
- { PCI_DEVICE(PCI_VENDOR_ID_AMD, 0x1103) },
- { PCI_DEVICE(PCI_VENDOR_ID_AMD, 0x1203) },
- {}
-};
-#endif
-
unsigned short num_cache_leaves;

/* AMD doesn't have CPUID4. Emulate it here to report the same
@@ -291,6 +286,12 @@ amd_check_l3_disable(int index, struct _cpuid4_info_regs *this_leaf)
{
if (index < 3)
return;
+ if (boot_cpu_data.x86 == 0x11)
+ return;
+
+ if ((boot_cpu_data.x86 == 0x10) && (boot_cpu_data.x86_model < 0x15))
+ return;
+
this_leaf->can_disable = 1;
}

@@ -639,6 +640,64 @@ static ssize_t show_##file_name \
return sprintf (buf, "%lu\n", (unsigned long)this_leaf->object + val); \
}

+static ssize_t show_cache_disable(struct _cpuid4_info *this_leaf, char *buf,
+ unsigned int index)
+{
+ int node = cpu_to_node(first_cpu(this_leaf->shared_cpu_map));
+ struct pci_dev *dev = k8_northbridges[node];
+ unsigned int reg = 0;
+
+ if (!this_leaf->can_disable)
+ return -EINVAL;
+
+ pci_read_config_dword(dev, 0x1BC + index * 4, &reg);
+ return sprintf(buf, "%x\n", reg);
+}
+
+#define SHOW_CACHE_DISABLE(index) \
+static ssize_t \
+show_cache_disable_##index(struct _cpuid4_info *this_leaf, char *buf) \
+{ \
+ return show_cache_disable(this_leaf, buf, index); \
+}
+
+static ssize_t
+store_cache_disable(struct _cpuid4_info *this_leaf, const char *buf,
+ size_t count, unsigned int index)
+{
+ int node = cpu_to_node(first_cpu(this_leaf->shared_cpu_map));
+ struct pci_dev *dev = k8_northbridges[node];
+ unsigned long val = 0;
+
+ if (!this_leaf->can_disable)
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (strict_strtoul(buf, 10, &val) < 0)
+ return -EINVAL;
+
+ val |= 0xc0000000;
+ pci_write_config_dword(dev, 0x1BC + index * 4, val & ~0x40000000);
+ wbinvd();
+ pci_write_config_dword(dev, 0x1BC + index * 4, val);
+ return count;
+}
+
+#define STORE_CACHE_DISABLE(index) \
+static ssize_t \
+store_cache_disable_##index(struct _cpuid4_info *this_leaf, \
+ const char *buf, size_t count) \
+{ \
+ return store_cache_disable(this_leaf, buf, count, index); \
+}
+
+SHOW_CACHE_DISABLE(0)
+STORE_CACHE_DISABLE(0)
+SHOW_CACHE_DISABLE(1)
+STORE_CACHE_DISABLE(1)
+
show_one_plus(level, eax.split.level, 0);
show_one_plus(coherency_line_size, ebx.split.coherency_line_size, 1);
show_one_plus(physical_line_partition, ebx.split.physical_line_partition, 1);
@@ -696,98 +755,6 @@ static ssize_t show_type(struct _cpuid4_info *this_leaf, char *buf)
#define to_object(k) container_of(k, struct _index_kobject, kobj)
#define to_attr(a) container_of(a, struct _cache_attr, attr)

-#ifdef CONFIG_PCI
-static struct pci_dev *get_k8_northbridge(int node)
-{
- struct pci_dev *dev = NULL;
- int i;
-
- for (i = 0; i <= node; i++) {
- do {
- dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
- if (!dev)
- break;
- } while (!pci_match_id(&k8_nb_id[0], dev));
- if (!dev)
- break;
- }
- return dev;
-}
-#else
-static struct pci_dev *get_k8_northbridge(int node)
-{
- return NULL;
-}
-#endif
-
-static ssize_t show_cache_disable(struct _cpuid4_info *this_leaf, char *buf)
-{
- const struct cpumask *mask = to_cpumask(this_leaf->shared_cpu_map);
- int node = cpu_to_node(cpumask_first(mask));
- struct pci_dev *dev = NULL;
- ssize_t ret = 0;
- int i;
-
- if (!this_leaf->can_disable)
- return sprintf(buf, "Feature not enabled\n");
-
- dev = get_k8_northbridge(node);
- if (!dev) {
- printk(KERN_ERR "Attempting AMD northbridge operation on a system with no northbridge\n");
- return -EINVAL;
- }
-
- for (i = 0; i < 2; i++) {
- unsigned int reg;
-
- pci_read_config_dword(dev, 0x1BC + i * 4, &reg);
-
- ret += sprintf(buf, "%sEntry: %d\n", buf, i);
- ret += sprintf(buf, "%sReads: %s\tNew Entries: %s\n",
- buf,
- reg & 0x80000000 ? "Disabled" : "Allowed",
- reg & 0x40000000 ? "Disabled" : "Allowed");
- ret += sprintf(buf, "%sSubCache: %x\tIndex: %x\n",
- buf, (reg & 0x30000) >> 16, reg & 0xfff);
- }
- return ret;
-}
-
-static ssize_t
-store_cache_disable(struct _cpuid4_info *this_leaf, const char *buf,
- size_t count)
-{
- const struct cpumask *mask = to_cpumask(this_leaf->shared_cpu_map);
- int node = cpu_to_node(cpumask_first(mask));
- struct pci_dev *dev = NULL;
- unsigned int ret, index, val;
-
- if (!this_leaf->can_disable)
- return 0;
-
- if (strlen(buf) > 15)
- return -EINVAL;
-
- ret = sscanf(buf, "%x %x", &index, &val);
- if (ret != 2)
- return -EINVAL;
- if (index > 1)
- return -EINVAL;
-
- val |= 0xc0000000;
- dev = get_k8_northbridge(node);
- if (!dev) {
- printk(KERN_ERR "Attempting AMD northbridge operation on a system with no northbridge\n");
- return -EINVAL;
- }
-
- pci_write_config_dword(dev, 0x1BC + index * 4, val & ~0x40000000);
- wbinvd();
- pci_write_config_dword(dev, 0x1BC + index * 4, val);
-
- return 1;
-}
-
struct _cache_attr {
struct attribute attr;
ssize_t (*show)(struct _cpuid4_info *, char *);
@@ -808,7 +775,11 @@ define_one_ro(size);
define_one_ro(shared_cpu_map);
define_one_ro(shared_cpu_list);

-static struct _cache_attr cache_disable = __ATTR(cache_disable, 0644, show_cache_disable, store_cache_disable);
+static struct _cache_attr cache_disable_0 = __ATTR(cache_disable_0, 0644,
+ show_cache_disable_0, store_cache_disable_0);
+static struct _cache_attr cache_disable_1 = __ATTR(cache_disable_1, 0644,
+ show_cache_disable_1, store_cache_disable_1);
+

static struct attribute * default_attrs[] = {
&type.attr,
@@ -820,7 +791,8 @@ static struct attribute * default_attrs[] = {
&size.attr,
&shared_cpu_map.attr,
&shared_cpu_list.attr,
- &cache_disable.attr,
+ &cache_disable_0.attr,
+ &cache_disable_1.attr,
NULL
};

-------------------------------------------------------


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