x86: AMD microcode patch loading support

This patch introduces microcode patch loading for AMD
processors. It is based on previous corresponding work
for Intel processors.

It hooks into the general patch loading module. Main
difference is that a container file format is used to hold
all patch data for multiple processors as well as an
equivalent CPU table, which comes seperately, as opposed
to Intel's microcode patching solution.

Kconfig and Makefile have been changed provice config
and build option for new source file.

Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 521 insertions, 0 deletions

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
new file mode 100644
index 0000000..db199e3
--- /dev/null
+++ b/arch/x86/kernel/microcode_amd.c
@@ -0,0 +1,521 @@
+/*
+ *  AMD CPU Microcode Update Driver for Linux
+ *  Copyright (C) 2008 Advanced Micro Devices Inc.
+ *
+ *  Author: Peter Oruba <peter.oruba@amd.com>
+ *
+ *  Based on work by:
+ *  Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
+ *
+ *  This driver allows to upgrade microcode on AMD
+ *  family 0x10 and 0x11 processors.
+ *
+ *  Licensed unter the terms of the GNU General Public
+ *  License version 2. See file COPYING for details.
+*/
+
+#include <linux/capability.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/cpumask.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/miscdevice.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/mutex.h>
+#include <linux/cpu.h>
+#include <linux/firmware.h>
+#include <linux/platform_device.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+
+#include <asm/msr.h>
+#include <asm/uaccess.h>
+#include <asm/processor.h>
+#include <asm/microcode.h>
+
+MODULE_DESCRIPTION("AMD Microcode Update Driver");
+MODULE_AUTHOR("Peter Oruba <peter.oruba@amd.com>");
+MODULE_LICENSE("GPLv2");
+
+#define UCODE_MAGIC                0x00414d44
+#define UCODE_EQUIV_CPU_TABLE_TYPE 0x00000000
+#define UCODE_UCODE_TYPE           0x00000001
+
+#define UCODE_MAX_SIZE          (2048)
+#define DEFAULT_UCODE_DATASIZE	(896)	  /* 896 bytes */
+#define MC_HEADER_SIZE		(sizeof(struct microcode_header_amd))	  /* 64 bytes */
+#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) /* 960 bytes */
+#define DWSIZE			(sizeof(u32))
+/* For now we support a fixed ucode total size only */
+#define get_totalsize(mc) \
+	((((struct microcode_amd *)mc)->hdr.mc_patch_data_len * 28) \
+	 + MC_HEADER_SIZE)
+
+extern int microcode_init(void *opaque, struct module *module);
+extern void microcode_exit(void);
+
+/* serialize access to the physical write */
+static DEFINE_SPINLOCK(microcode_update_lock);
+
+/* no concurrent ->write()s are allowed on /dev/cpu/microcode */
+extern struct mutex (microcode_mutex);
+
+struct equiv_cpu_entry *equiv_cpu_table;
+
+extern struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
+
+static void collect_cpu_info_amd(int cpu)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+	/* We should bind the task to the CPU */
+	BUG_ON(raw_smp_processor_id() != cpu);
+	uci->rev = 0;
+	uci->pf = 0;
+	uci->mc.mc_amd = NULL;
+	uci->valid = 1;
+
+	if (c->x86_vendor != X86_VENDOR_AMD || c->x86 < 0x10) {
+		printk(KERN_ERR "microcode: CPU%d not a capable AMD processor\n",
+		       cpu);
+		uci->valid = 0;
+		return;
+	}
+
+	asm volatile("movl %1, %%ecx; rdmsr"
+		     : "=a" (uci->rev)
+		     : "i" (0x0000008B) : "ecx");
+
+	printk(KERN_INFO "microcode: collect_cpu_info_amd : patch_id=0x%x\n",
+	       uci->rev);
+}
+
+static int get_matching_microcode_amd(void *mc, int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	struct microcode_header_amd *mc_header = mc;
+	unsigned long total_size = get_totalsize(mc_header);
+	void *new_mc;
+	struct pci_dev *nb_pci_dev, *sb_pci_dev;
+	unsigned int current_cpu_id;
+	unsigned int equiv_cpu_id = 0x00;
+	unsigned int i = 0;
+
+	/* We should bind the task to the CPU */
+	BUG_ON(cpu != raw_smp_processor_id());
+
+	/* This is a tricky part. We might be called from a write operation */
+	/* to the device file instead of the usual process of firmware */
+	/* loading. This routine needs to be able to distinguish both */
+/* cases. This is done by checking if there alread is a equivalent */
+	/* CPU table installed. If not, we're written through */
+	/* /dev/cpu/microcode. */
+/* Since we ignore all checks. The error case in which going through */
+/* firmware loading and that table is not loaded has already been */
+	/* checked earlier. */
+	if (equiv_cpu_table == NULL) {
+		printk(KERN_INFO "microcode: CPU%d microcode update with "
+		       "version 0x%x (current=0x%x)\n",
+		       cpu, mc_header->patch_id, uci->rev);
+		goto out;
+	}
+
+	current_cpu_id = cpuid_eax(0x00000001);
+
+	while (equiv_cpu_table[i].installed_cpu != 0) {
+		if (current_cpu_id == equiv_cpu_table[i].installed_cpu) {
+			equiv_cpu_id = equiv_cpu_table[i].equiv_cpu;
+			break;
+		}
+		i++;
+	}
+
+	if (!equiv_cpu_id) {
+		printk(KERN_ERR "microcode: CPU%d cpu_id "
+		       "not found in equivalent cpu table \n", cpu);
+		return 0;
+	}
+
+	if ((mc_header->processor_rev_id[0]) != (equiv_cpu_id & 0xff)) {
+		printk(KERN_ERR
+			"microcode: CPU%d patch does not match "
+			"(patch is %x, cpu extended is %x) \n",
+			cpu, mc_header->processor_rev_id[0],
+			(equiv_cpu_id & 0xff));
+		return 0;
+	}
+
+	if ((mc_header->processor_rev_id[1]) != ((equiv_cpu_id >> 16) & 0xff)) {
+		printk(KERN_ERR "microcode: CPU%d patch does not match "
+			"(patch is %x, cpu base id is %x) \n",
+			cpu, mc_header->processor_rev_id[1],
+			((equiv_cpu_id >> 16) & 0xff));
+
+		return 0;
+	}
+
+	/* ucode may be northbridge specific */
+	if (mc_header->nb_dev_id) {
+		nb_pci_dev = pci_get_device(PCI_VENDOR_ID_AMD,
+					    (mc_header->nb_dev_id & 0xff),
+					    NULL);
+		if ((!nb_pci_dev) ||
+		    (mc_header->nb_rev_id != nb_pci_dev->revision)) {
+			printk(KERN_ERR "microcode: CPU%d NB mismatch \n", cpu);
+			pci_dev_put(nb_pci_dev);
+			return 0;
+		}
+		pci_dev_put(nb_pci_dev);
+	}
+
+	/* ucode may be southbridge specific */
+	if (mc_header->sb_dev_id) {
+		sb_pci_dev = pci_get_device(PCI_VENDOR_ID_AMD,
+					    (mc_header->sb_dev_id & 0xff),
+					    NULL);
+		if ((!sb_pci_dev) ||
+		    (mc_header->sb_rev_id != sb_pci_dev->revision)) {
+			printk(KERN_ERR "microcode: CPU%d SB mismatch \n", cpu);
+			pci_dev_put(sb_pci_dev);
+			return 0;
+		}
+		pci_dev_put(sb_pci_dev);
+	}
+
+	if (mc_header->patch_id <= uci->rev)
+		return 0;
+
+	printk(KERN_INFO "microcode: CPU%d found a matching microcode "
+	       "update with version 0x%x (current=0x%x)\n",
+	       cpu, mc_header->patch_id, uci->rev);
+
+out:
+	new_mc = vmalloc(UCODE_MAX_SIZE);
+	if (!new_mc) {
+		printk(KERN_ERR "microcode: error, can't allocate memory\n");
+		return -ENOMEM;
+	}
+	memset(new_mc, 0, UCODE_MAX_SIZE);
+
+	/* free previous update file */
+	vfree(uci->mc.mc_amd);
+
+	memcpy(new_mc, mc, total_size);
+
+	uci->mc.mc_amd = new_mc;
+	return 1;
+}
+
+static void apply_microcode_amd(int cpu)
+{
+	unsigned long flags;
+	unsigned int eax, edx;
+	unsigned int rev;
+	int cpu_num = raw_smp_processor_id();
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
+
+	/* We should bind the task to the CPU */
+	BUG_ON(cpu_num != cpu);
+
+	if (uci->mc.mc_amd == NULL)
+		return;
+
+	spin_lock_irqsave(&microcode_update_lock, flags);
+
+	edx = (unsigned int)(((unsigned long)
+			      &(uci->mc.mc_amd->hdr.data_code)) >> 32);
+	eax = (unsigned int)(((unsigned long)
+			      &(uci->mc.mc_amd->hdr.data_code)) & 0xffffffffL);
+
+	asm volatile("movl %0, %%ecx; wrmsr" :
+		     : "i" (0xc0010020), "a" (eax), "d" (edx) : "ecx");
+
+	/* get patch id after patching */
+	asm volatile("movl %1, %%ecx; rdmsr"
+		     : "=a" (rev)
+		     : "i" (0x0000008B) : "ecx");
+
+	spin_unlock_irqrestore(&microcode_update_lock, flags);
+
+	/* check current patch id and patch's id for match */
+	if (rev != uci->mc.mc_amd->hdr.patch_id) {
+		printk(KERN_ERR "microcode: CPU%d update from revision "
+		       "0x%x to 0x%x failed\n", cpu_num,
+		       uci->mc.mc_amd->hdr.patch_id, rev);
+		return;
+	}
+
+	printk(KERN_INFO "microcode: CPU%d updated from revision "
+	       "0x%x to 0x%x \n",
+	       cpu_num, uci->rev, uci->mc.mc_amd->hdr.patch_id);
+
+	uci->rev = rev;
+}
+
+#ifdef CONFIG_MICROCODE_OLD_INTERFACE
+extern void __user *user_buffer;        /* user area microcode data buffer */
+extern unsigned int user_buffer_size;   /* it's size */
+
+static long get_next_ucode_amd(void **mc, long offset)
+{
+	struct microcode_header_amd mc_header;
+	unsigned long total_size;
+
+	/* No more data */
+	if (offset >= user_buffer_size)
+		return 0;
+	if (copy_from_user(&mc_header, user_buffer + offset, MC_HEADER_SIZE)) {
+		printk(KERN_ERR "microcode: error! Can not read user data\n");
+		return -EFAULT;
+	}
+	total_size = get_totalsize(&mc_header);
+	if (offset + total_size > user_buffer_size) {
+		printk(KERN_ERR "microcode: error! Bad total size in microcode "
+		       "data file\n");
+		return -EINVAL;
+	}
+	*mc = vmalloc(UCODE_MAX_SIZE);
+	if (!*mc)
+		return -ENOMEM;
+	memset(*mc, 0, UCODE_MAX_SIZE);
+
+	if (copy_from_user(*mc, user_buffer + offset, total_size)) {
+		printk(KERN_ERR "microcode: error! Can not read user data\n");
+		vfree(*mc);
+		return -EFAULT;
+	}
+	return offset + total_size;
+}
+#else
+#define get_next_ucode_amd() NULL
+#endif
+
+static long get_next_ucode_from_buffer_amd(void **mc, void *buf,
+				       unsigned long size, long offset)
+{
+	struct microcode_header_amd *mc_header;
+	unsigned long total_size;
+	unsigned char *buf_pos = buf;
+
+	/* No more data */
+	if (offset >= size)
+		return 0;
+
+	if (buf_pos[offset] != UCODE_UCODE_TYPE) {
+		printk(KERN_ERR "microcode: error! "
+		       "Wrong microcode payload type field\n");
+		return -EINVAL;
+	}
+
+	mc_header = (struct microcode_header_amd *)(&buf_pos[offset+8]);
+
+	total_size = (unsigned long) (buf_pos[offset+4] +
+				      (buf_pos[offset+5] << 8));
+
+	printk(KERN_INFO "microcode: size %lu, total_size %lu, offset %ld\n",
+		size, total_size, offset);
+
+	if (offset + total_size > size) {
+		printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
+		return -EINVAL;
+	}
+
+	*mc = vmalloc(UCODE_MAX_SIZE);
+	if (!*mc) {
+		printk(KERN_ERR "microcode: error! "
+		       "Can not allocate memory for microcode patch\n");
+		return -ENOMEM;
+	}
+
+	memset(*mc, 0, UCODE_MAX_SIZE);
+	memcpy(*mc, buf + offset + 8, total_size);
+
+	return offset + total_size + 8;
+}
+
+static long install_equiv_cpu_table(void *buf, unsigned long size, long offset)
+{
+	unsigned int *buf_pos = buf;
+
+	/* No more data */
+	if (offset >= size)
+		return 0;
+
+	if (buf_pos[1] != UCODE_EQUIV_CPU_TABLE_TYPE) {
+		printk(KERN_ERR "microcode: error! "
+		       "Wrong microcode equivalnet cpu table type field\n");
+		return 0;
+	}
+
+	if (size == 0) {
+		printk(KERN_ERR "microcode: error! "
+		       "Wrong microcode equivalnet cpu table length\n");
+		return 0;
+	}
+
+	equiv_cpu_table = (struct equiv_cpu_entry *) vmalloc(size);
+	if (!equiv_cpu_table) {
+		printk(KERN_ERR "microcode: error, can't allocate memory for equiv CPU table\n");
+		return 0;
+	}
+
+	memset(equiv_cpu_table, 0, size);
+	memcpy(equiv_cpu_table, &buf_pos[3], size);
+
+	return size + 12; /* add header length */
+}
+
+/* fake device for request_firmware */
+extern struct platform_device *microcode_pdev;
+
+static int cpu_request_microcode_amd(int cpu)
+{
+	char name[30];
+	const struct firmware *firmware;
+	void *buf;
+	unsigned int *buf_pos;
+	unsigned long size;
+	long offset = 0;
+	int error;
+	void *mc;
+
+	/* We should bind the task to the CPU */
+	BUG_ON(cpu != raw_smp_processor_id());
+
+	sprintf(name, "amd-ucode/microcode_amd.bin");
+	error = request_firmware(&firmware, "amd-ucode/microcode_amd.bin",
+				 &microcode_pdev->dev);
+	if (error) {
+		printk(KERN_ERR "microcode: ucode data file %s load failed\n",
+		       name);
+		return error;
+	}
+
+	buf_pos = buf = firmware->data;
+	size = firmware->size;
+
+	if (buf_pos[0] != UCODE_MAGIC) {
+		printk(KERN_ERR "microcode: error! Wrong microcode patch file magic\n");
+		return -EINVAL;
+	}
+
+	offset = install_equiv_cpu_table(buf, buf_pos[2], offset);
+
+	if (!offset) {
+		printk(KERN_ERR "microcode: installing equivalent cpu table failed\n");
+		return -EINVAL;
+	}
+
+	while ((offset =
+		get_next_ucode_from_buffer_amd(&mc, buf, size, offset)) > 0) {
+		error = get_matching_microcode_amd(mc, cpu);
+		if (error < 0)
+			break;
+		/*
+		 * It's possible the data file has multiple matching ucode,
+		 * lets keep searching till the latest version
+		 */
+		if (error == 1) {
+			apply_microcode_amd(cpu);
+			error = 0;
+		}
+		vfree(mc);
+	}
+	if (offset > 0) {
+		vfree(mc);
+		vfree(equiv_cpu_table);
+		equiv_cpu_table = NULL;
+	}
+	if (offset < 0)
+		error = offset;
+	release_firmware(firmware);
+
+	return error;
+}
+
+static int apply_microcode_check_cpu_amd(int cpu)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	unsigned int rev;
+	cpumask_t old;
+	cpumask_of_cpu_ptr(newmask, cpu);
+	int err = 0;
+
+	/* Check if the microcode is available */
+	if (!uci->mc.mc_amd)
+		return 0;
+
+	old = current->cpus_allowed;
+	set_cpus_allowed(current, newmask);
+
+	/* Check if the microcode we have in memory matches the CPU */
+	if (c->x86_vendor != X86_VENDOR_AMD || c->x86 < 16)
+		err = -EINVAL;
+
+	if (!err) {
+		asm volatile("movl %1, %%ecx; rdmsr"
+		     : "=a" (rev)
+		     : "i" (0x0000008B) : "ecx");
+
+		if (uci->rev != rev)
+			err = -EINVAL;
+	}
+
+	if (!err)
+		apply_microcode_amd(cpu);
+	else
+		printk(KERN_ERR "microcode: Could not apply microcode to CPU%d:"
+		       " rev=0x%x\n",
+		       cpu,  uci->rev);
+
+	set_cpus_allowed(current, old);
+	return err;
+}
+
+static void microcode_fini_cpu_amd(int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+	mutex_lock(&microcode_mutex);
+	uci->valid = 0;
+	vfree(uci->mc.mc_amd);
+	uci->mc.mc_amd = NULL;
+	mutex_unlock(&microcode_mutex);
+}
+
+static struct microcode_ops microcode_amd_ops = {
+	.get_next_ucode                   = get_next_ucode_amd,
+	.get_matching_microcode           = get_matching_microcode_amd,
+	.microcode_sanity_check           = NULL,
+	.apply_microcode_check_cpu        = apply_microcode_check_cpu_amd,
+	.cpu_request_microcode            = cpu_request_microcode_amd,
+	.collect_cpu_info                 = collect_cpu_info_amd,
+	.apply_microcode                  = apply_microcode_amd,
+	.microcode_fini_cpu               = microcode_fini_cpu_amd,
+};
+
+static int __init microcode_amd_module_init(void)
+{
+	struct cpuinfo_x86 *c = &cpu_data(get_cpu());
+
+	equiv_cpu_table = NULL;
+	if (c->x86_vendor == X86_VENDOR_AMD)
+		return microcode_init(&microcode_amd_ops, THIS_MODULE);
+	else
+		return -ENODEV;
+}
+
+static void __exit microcode_amd_module_exit(void)
+{
+	microcode_exit();
+}
+
+module_init(microcode_amd_module_init)
+module_exit(microcode_amd_module_exit)