x86: microcode update support for AMD CPUs

Microcode update support for AMD CPUs Family10h and Family11h.
It is based on a patch for Linux which is on its way for 2.6.28.

Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>

1 files changed, 366 insertions, 0 deletions

diff --git a/xen/arch/x86/microcode_amd.c b/xen/arch/x86/microcode_amd.c
new file mode 100644
index 0000000000..d2198d5838
--- /dev/null
+++ b/xen/arch/x86/microcode_amd.c
@@ -0,0 +1,366 @@
+/*
+ *  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 <xen/config.h>
+#include <xen/lib.h>
+#include <xen/kernel.h>
+#include <xen/init.h>
+#include <xen/sched.h>
+#include <xen/smp.h>
+#include <xen/spinlock.h>
+
+#include <asm/msr.h>
+#include <asm/uaccess.h>
+#include <asm/processor.h>
+#include <asm/microcode.h>
+
+
+#define pr_debug(x...) ((void)0)
+#define DEFINE_MUTEX(_m) DEFINE_SPINLOCK(_m)
+#define mutex_lock(_m) spin_lock(_m)
+#define mutex_unlock(_m) spin_unlock(_m)
+#define vmalloc(_s) xmalloc_bytes(_s)
+#define vfree(_p) xfree(_p)
+
+
+#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)
+#define MC_HEADER_SIZE		(sizeof(struct microcode_header_amd))
+#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
+#define DWSIZE			(sizeof(uint32_t))
+/* 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)
+
+/* serialize access to the physical write */
+static DEFINE_SPINLOCK(microcode_update_lock);
+
+struct equiv_cpu_entry *equiv_cpu_table;
+
+static long install_equiv_cpu_table(const void *, uint32_t, long);
+
+static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
+{
+	struct cpuinfo_x86 *c = &cpu_data[cpu];
+
+	memset(csig, 0, sizeof(*csig));
+
+	if (c->x86_vendor != X86_VENDOR_AMD || c->x86 < 0x10) {
+		printk(KERN_ERR "microcode: CPU%d not a capable AMD processor\n",
+		       cpu);
+		return -1;
+	}
+
+	asm volatile("movl %1, %%ecx; rdmsr"
+		     : "=a" (csig->rev)
+		     : "i" (MSR_AMD_PATCHLEVEL) : "ecx");
+
+	printk(KERN_INFO "microcode: collect_cpu_info_amd : patch_id=0x%x\n",
+		csig->rev);
+
+	return 0;
+}
+
+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;
+	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 already 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->cpu_sig.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_INFO
+			"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_INFO "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;
+	}
+
+	if (mc_header->patch_id <= uci->cpu_sig.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->cpu_sig.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 int 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;
+	unsigned long addr;
+
+	/* We should bind the task to the CPU */
+	BUG_ON(cpu_num != cpu);
+
+	if (uci->mc.mc_amd == NULL)
+		return -EINVAL;
+
+	spin_lock_irqsave(&microcode_update_lock, flags);
+
+	addr = (unsigned long)&uci->mc.mc_amd->hdr.data_code;
+	edx = (unsigned int)((unsigned long)(addr >> 32));
+	eax = (unsigned int)((unsigned long)(addr & 0xffffffff));
+
+	asm volatile("movl %0, %%ecx; wrmsr" :
+		     : "i" (MSR_AMD_PATCHLOADER), "a" (eax), "d" (edx) : "ecx");
+
+	/* get patch id after patching */
+	asm volatile("movl %1, %%ecx; rdmsr"
+		     : "=a" (rev)
+		     : "i" (MSR_AMD_PATCHLEVEL) : "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 -EIO;
+	}
+
+	printk("microcode: CPU%d updated from revision "
+	       "0x%x to 0x%x \n",
+	       cpu_num, uci->cpu_sig.rev, uci->mc.mc_amd->hdr.patch_id);
+
+	uci->cpu_sig.rev = rev;
+
+	return 0;
+}
+
+static long get_next_ucode_from_buffer_amd(void **mc, const void *buf,
+				       unsigned long size, long offset)
+{
+	struct microcode_header_amd *mc_header;
+	unsigned long total_size;
+	const uint8_t *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, (const void *)(buf + offset + 8), total_size);
+
+	return offset + total_size + 8;
+}
+
+static long install_equiv_cpu_table(const void *buf,
+				uint32_t size, long offset)
+{
+	const uint32_t *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, (const void *)&buf_pos[3], size);
+
+	return size + 12; /* add header length */
+}
+
+static int cpu_request_microcode_amd(int cpu, const void *buf,
+				size_t size)
+{
+	const uint32_t *buf_pos;
+	long offset = 0;
+	int error = 0;
+	void *mc;
+
+	/* We should bind the task to the CPU */
+	BUG_ON(cpu != raw_smp_processor_id());
+
+	buf_pos = (const uint32_t *)buf;
+
+	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, (uint32_t)(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;
+
+	return error;
+}
+
+static void microcode_fini_cpu_amd(int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+	vfree(uci->mc.mc_amd);
+	uci->mc.mc_amd = NULL;
+}
+
+static struct microcode_ops microcode_amd_ops = {
+	.get_matching_microcode           = get_matching_microcode_amd,
+	.microcode_sanity_check           = NULL,
+	.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,
+};
+
+int microcode_init_amd(struct cpuinfo_x86 *c)
+{
+	microcode_ops = &microcode_amd_ops;
+	return 0;
+}
+