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-rw-r--r--arch/x86/cpu/i386/cpu.c534
1 files changed, 534 insertions, 0 deletions
diff --git a/arch/x86/cpu/i386/cpu.c b/arch/x86/cpu/i386/cpu.c
new file mode 100644
index 0000000000..09a5b919e0
--- /dev/null
+++ b/arch/x86/cpu/i386/cpu.c
@@ -0,0 +1,534 @@
+/*
+ * (C) Copyright 2008-2011
+ * Graeme Russ, <graeme.russ@gmail.com>
+ *
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * Part of this file is adapted from coreboot
+ * src/arch/x86/lib/cpu.c
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <asm/control_regs.h>
+#include <asm/cpu.h>
+#include <asm/mp.h>
+#include <asm/msr.h>
+#include <asm/mtrr.h>
+#include <asm/processor-flags.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * Constructor for a conventional segment GDT (or LDT) entry
+ * This is a macro so it can be used in initialisers
+ */
+#define GDT_ENTRY(flags, base, limit) \
+ ((((base) & 0xff000000ULL) << (56-24)) | \
+ (((flags) & 0x0000f0ffULL) << 40) | \
+ (((limit) & 0x000f0000ULL) << (48-16)) | \
+ (((base) & 0x00ffffffULL) << 16) | \
+ (((limit) & 0x0000ffffULL)))
+
+struct gdt_ptr {
+ u16 len;
+ u32 ptr;
+} __packed;
+
+struct cpu_device_id {
+ unsigned vendor;
+ unsigned device;
+};
+
+struct cpuinfo_x86 {
+ uint8_t x86; /* CPU family */
+ uint8_t x86_vendor; /* CPU vendor */
+ uint8_t x86_model;
+ uint8_t x86_mask;
+};
+
+/*
+ * List of cpu vendor strings along with their normalized
+ * id values.
+ */
+static const struct {
+ int vendor;
+ const char *name;
+} x86_vendors[] = {
+ { X86_VENDOR_INTEL, "GenuineIntel", },
+ { X86_VENDOR_CYRIX, "CyrixInstead", },
+ { X86_VENDOR_AMD, "AuthenticAMD", },
+ { X86_VENDOR_UMC, "UMC UMC UMC ", },
+ { X86_VENDOR_NEXGEN, "NexGenDriven", },
+ { X86_VENDOR_CENTAUR, "CentaurHauls", },
+ { X86_VENDOR_RISE, "RiseRiseRise", },
+ { X86_VENDOR_TRANSMETA, "GenuineTMx86", },
+ { X86_VENDOR_TRANSMETA, "TransmetaCPU", },
+ { X86_VENDOR_NSC, "Geode by NSC", },
+ { X86_VENDOR_SIS, "SiS SiS SiS ", },
+};
+
+static void load_ds(u32 segment)
+{
+ asm volatile("movl %0, %%ds" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_es(u32 segment)
+{
+ asm volatile("movl %0, %%es" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_fs(u32 segment)
+{
+ asm volatile("movl %0, %%fs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_gs(u32 segment)
+{
+ asm volatile("movl %0, %%gs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_ss(u32 segment)
+{
+ asm volatile("movl %0, %%ss" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_gdt(const u64 *boot_gdt, u16 num_entries)
+{
+ struct gdt_ptr gdt;
+
+ gdt.len = (num_entries * X86_GDT_ENTRY_SIZE) - 1;
+ gdt.ptr = (ulong)boot_gdt;
+
+ asm volatile("lgdtl %0\n" : : "m" (gdt));
+}
+
+void arch_setup_gd(gd_t *new_gd)
+{
+ u64 *gdt_addr;
+
+ gdt_addr = new_gd->arch.gdt;
+
+ /*
+ * CS: code, read/execute, 4 GB, base 0
+ *
+ * Some OS (like VxWorks) requires GDT entry 1 to be the 32-bit CS
+ */
+ gdt_addr[X86_GDT_ENTRY_UNUSED] = GDT_ENTRY(0xc09b, 0, 0xfffff);
+ gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
+
+ /* DS: data, read/write, 4 GB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff);
+
+ /* FS: data, read/write, 4 GB, base (Global Data Pointer) */
+ new_gd->arch.gd_addr = new_gd;
+ gdt_addr[X86_GDT_ENTRY_32BIT_FS] = GDT_ENTRY(0xc093,
+ (ulong)&new_gd->arch.gd_addr, 0xfffff);
+
+ /* 16-bit CS: code, read/execute, 64 kB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x009b, 0, 0x0ffff);
+
+ /* 16-bit DS: data, read/write, 64 kB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x0093, 0, 0x0ffff);
+
+ gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_CS] = GDT_ENTRY(0x809b, 0, 0xfffff);
+ gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_DS] = GDT_ENTRY(0x8093, 0, 0xfffff);
+
+ load_gdt(gdt_addr, X86_GDT_NUM_ENTRIES);
+ load_ds(X86_GDT_ENTRY_32BIT_DS);
+ load_es(X86_GDT_ENTRY_32BIT_DS);
+ load_gs(X86_GDT_ENTRY_32BIT_DS);
+ load_ss(X86_GDT_ENTRY_32BIT_DS);
+ load_fs(X86_GDT_ENTRY_32BIT_FS);
+}
+
+#ifdef CONFIG_HAVE_FSP
+/*
+ * Setup FSP execution environment GDT
+ *
+ * Per Intel FSP external architecture specification, before calling any FSP
+ * APIs, we need make sure the system is in flat 32-bit mode and both the code
+ * and data selectors should have full 4GB access range. Here we reuse the one
+ * we used in arch/x86/cpu/start16.S, and reload the segement registers.
+ */
+void setup_fsp_gdt(void)
+{
+ load_gdt((const u64 *)(gdt_rom + CONFIG_RESET_SEG_START), 4);
+ load_ds(X86_GDT_ENTRY_32BIT_DS);
+ load_ss(X86_GDT_ENTRY_32BIT_DS);
+ load_es(X86_GDT_ENTRY_32BIT_DS);
+ load_fs(X86_GDT_ENTRY_32BIT_DS);
+ load_gs(X86_GDT_ENTRY_32BIT_DS);
+}
+#endif
+
+/*
+ * Cyrix CPUs without cpuid or with cpuid not yet enabled can be detected
+ * by the fact that they preserve the flags across the division of 5/2.
+ * PII and PPro exhibit this behavior too, but they have cpuid available.
+ */
+
+/*
+ * Perform the Cyrix 5/2 test. A Cyrix won't change
+ * the flags, while other 486 chips will.
+ */
+static inline int test_cyrix_52div(void)
+{
+ unsigned int test;
+
+ __asm__ __volatile__(
+ "sahf\n\t" /* clear flags (%eax = 0x0005) */
+ "div %b2\n\t" /* divide 5 by 2 */
+ "lahf" /* store flags into %ah */
+ : "=a" (test)
+ : "0" (5), "q" (2)
+ : "cc");
+
+ /* AH is 0x02 on Cyrix after the divide.. */
+ return (unsigned char) (test >> 8) == 0x02;
+}
+
+/*
+ * Detect a NexGen CPU running without BIOS hypercode new enough
+ * to have CPUID. (Thanks to Herbert Oppmann)
+ */
+static int deep_magic_nexgen_probe(void)
+{
+ int ret;
+
+ __asm__ __volatile__ (
+ " movw $0x5555, %%ax\n"
+ " xorw %%dx,%%dx\n"
+ " movw $2, %%cx\n"
+ " divw %%cx\n"
+ " movl $0, %%eax\n"
+ " jnz 1f\n"
+ " movl $1, %%eax\n"
+ "1:\n"
+ : "=a" (ret) : : "cx", "dx");
+ return ret;
+}
+
+static bool has_cpuid(void)
+{
+ return flag_is_changeable_p(X86_EFLAGS_ID);
+}
+
+static bool has_mtrr(void)
+{
+ return cpuid_edx(0x00000001) & (1 << 12) ? true : false;
+}
+
+static int build_vendor_name(char *vendor_name)
+{
+ struct cpuid_result result;
+ result = cpuid(0x00000000);
+ unsigned int *name_as_ints = (unsigned int *)vendor_name;
+
+ name_as_ints[0] = result.ebx;
+ name_as_ints[1] = result.edx;
+ name_as_ints[2] = result.ecx;
+
+ return result.eax;
+}
+
+static void identify_cpu(struct cpu_device_id *cpu)
+{
+ char vendor_name[16];
+ int i;
+
+ vendor_name[0] = '\0'; /* Unset */
+ cpu->device = 0; /* fix gcc 4.4.4 warning */
+
+ /* Find the id and vendor_name */
+ if (!has_cpuid()) {
+ /* Its a 486 if we can modify the AC flag */
+ if (flag_is_changeable_p(X86_EFLAGS_AC))
+ cpu->device = 0x00000400; /* 486 */
+ else
+ cpu->device = 0x00000300; /* 386 */
+ if ((cpu->device == 0x00000400) && test_cyrix_52div()) {
+ memcpy(vendor_name, "CyrixInstead", 13);
+ /* If we ever care we can enable cpuid here */
+ }
+ /* Detect NexGen with old hypercode */
+ else if (deep_magic_nexgen_probe())
+ memcpy(vendor_name, "NexGenDriven", 13);
+ }
+ if (has_cpuid()) {
+ int cpuid_level;
+
+ cpuid_level = build_vendor_name(vendor_name);
+ vendor_name[12] = '\0';
+
+ /* Intel-defined flags: level 0x00000001 */
+ if (cpuid_level >= 0x00000001) {
+ cpu->device = cpuid_eax(0x00000001);
+ } else {
+ /* Have CPUID level 0 only unheard of */
+ cpu->device = 0x00000400;
+ }
+ }
+ cpu->vendor = X86_VENDOR_UNKNOWN;
+ for (i = 0; i < ARRAY_SIZE(x86_vendors); i++) {
+ if (memcmp(vendor_name, x86_vendors[i].name, 12) == 0) {
+ cpu->vendor = x86_vendors[i].vendor;
+ break;
+ }
+ }
+}
+
+static inline void get_fms(struct cpuinfo_x86 *c, uint32_t tfms)
+{
+ c->x86 = (tfms >> 8) & 0xf;
+ c->x86_model = (tfms >> 4) & 0xf;
+ c->x86_mask = tfms & 0xf;
+ if (c->x86 == 0xf)
+ c->x86 += (tfms >> 20) & 0xff;
+ if (c->x86 >= 0x6)
+ c->x86_model += ((tfms >> 16) & 0xF) << 4;
+}
+
+u32 cpu_get_family_model(void)
+{
+ return gd->arch.x86_device & 0x0fff0ff0;
+}
+
+u32 cpu_get_stepping(void)
+{
+ return gd->arch.x86_mask;
+}
+
+int x86_cpu_init_f(void)
+{
+ const u32 em_rst = ~X86_CR0_EM;
+ const u32 mp_ne_set = X86_CR0_MP | X86_CR0_NE;
+
+ if (ll_boot_init()) {
+ /* initialize FPU, reset EM, set MP and NE */
+ asm ("fninit\n" \
+ "movl %%cr0, %%eax\n" \
+ "andl %0, %%eax\n" \
+ "orl %1, %%eax\n" \
+ "movl %%eax, %%cr0\n" \
+ : : "i" (em_rst), "i" (mp_ne_set) : "eax");
+ }
+
+ /* identify CPU via cpuid and store the decoded info into gd->arch */
+ if (has_cpuid()) {
+ struct cpu_device_id cpu;
+ struct cpuinfo_x86 c;
+
+ identify_cpu(&cpu);
+ get_fms(&c, cpu.device);
+ gd->arch.x86 = c.x86;
+ gd->arch.x86_vendor = cpu.vendor;
+ gd->arch.x86_model = c.x86_model;
+ gd->arch.x86_mask = c.x86_mask;
+ gd->arch.x86_device = cpu.device;
+
+ gd->arch.has_mtrr = has_mtrr();
+ }
+ /* Don't allow PCI region 3 to use memory in the 2-4GB memory hole */
+ gd->pci_ram_top = 0x80000000U;
+
+ /* Configure fixed range MTRRs for some legacy regions */
+ if (gd->arch.has_mtrr) {
+ u64 mtrr_cap;
+
+ mtrr_cap = native_read_msr(MTRR_CAP_MSR);
+ if (mtrr_cap & MTRR_CAP_FIX) {
+ /* Mark the VGA RAM area as uncacheable */
+ native_write_msr(MTRR_FIX_16K_A0000_MSR,
+ MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE),
+ MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE));
+
+ /*
+ * Mark the PCI ROM area as cacheable to improve ROM
+ * execution performance.
+ */
+ native_write_msr(MTRR_FIX_4K_C0000_MSR,
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
+ native_write_msr(MTRR_FIX_4K_C8000_MSR,
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
+ native_write_msr(MTRR_FIX_4K_D0000_MSR,
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
+ native_write_msr(MTRR_FIX_4K_D8000_MSR,
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+ MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
+
+ /* Enable the fixed range MTRRs */
+ msr_setbits_64(MTRR_DEF_TYPE_MSR, MTRR_DEF_TYPE_FIX_EN);
+ }
+ }
+
+#ifdef CONFIG_I8254_TIMER
+ /* Set up the i8254 timer if required */
+ i8254_init();
+#endif
+
+ return 0;
+}
+
+void x86_enable_caches(void)
+{
+ unsigned long cr0;
+
+ cr0 = read_cr0();
+ cr0 &= ~(X86_CR0_NW | X86_CR0_CD);
+ write_cr0(cr0);
+ wbinvd();
+}
+void enable_caches(void) __attribute__((weak, alias("x86_enable_caches")));
+
+void x86_disable_caches(void)
+{
+ unsigned long cr0;
+
+ cr0 = read_cr0();
+ cr0 |= X86_CR0_NW | X86_CR0_CD;
+ wbinvd();
+ write_cr0(cr0);
+ wbinvd();
+}
+void disable_caches(void) __attribute__((weak, alias("x86_disable_caches")));
+
+int dcache_status(void)
+{
+ return !(read_cr0() & X86_CR0_CD);
+}
+
+void cpu_enable_paging_pae(ulong cr3)
+{
+ __asm__ __volatile__(
+ /* Load the page table address */
+ "movl %0, %%cr3\n"
+ /* Enable pae */
+ "movl %%cr4, %%eax\n"
+ "orl $0x00000020, %%eax\n"
+ "movl %%eax, %%cr4\n"
+ /* Enable paging */
+ "movl %%cr0, %%eax\n"
+ "orl $0x80000000, %%eax\n"
+ "movl %%eax, %%cr0\n"
+ :
+ : "r" (cr3)
+ : "eax");
+}
+
+void cpu_disable_paging_pae(void)
+{
+ /* Turn off paging */
+ __asm__ __volatile__ (
+ /* Disable paging */
+ "movl %%cr0, %%eax\n"
+ "andl $0x7fffffff, %%eax\n"
+ "movl %%eax, %%cr0\n"
+ /* Disable pae */
+ "movl %%cr4, %%eax\n"
+ "andl $0xffffffdf, %%eax\n"
+ "movl %%eax, %%cr4\n"
+ :
+ :
+ : "eax");
+}
+
+static bool can_detect_long_mode(void)
+{
+ return cpuid_eax(0x80000000) > 0x80000000UL;
+}
+
+static bool has_long_mode(void)
+{
+ return cpuid_edx(0x80000001) & (1 << 29) ? true : false;
+}
+
+int cpu_has_64bit(void)
+{
+ return has_cpuid() && can_detect_long_mode() &&
+ has_long_mode();
+}
+
+#define PAGETABLE_SIZE (6 * 4096)
+
+/**
+ * build_pagetable() - build a flat 4GiB page table structure for 64-bti mode
+ *
+ * @pgtable: Pointer to a 24iKB block of memory
+ */
+static void build_pagetable(uint32_t *pgtable)
+{
+ uint i;
+
+ memset(pgtable, '\0', PAGETABLE_SIZE);
+
+ /* Level 4 needs a single entry */
+ pgtable[0] = (ulong)&pgtable[1024] + 7;
+
+ /* Level 3 has one 64-bit entry for each GiB of memory */
+ for (i = 0; i < 4; i++)
+ pgtable[1024 + i * 2] = (ulong)&pgtable[2048] + 0x1000 * i + 7;
+
+ /* Level 2 has 2048 64-bit entries, each repesenting 2MiB */
+ for (i = 0; i < 2048; i++)
+ pgtable[2048 + i * 2] = 0x183 + (i << 21UL);
+}
+
+int cpu_jump_to_64bit(ulong setup_base, ulong target)
+{
+ uint32_t *pgtable;
+
+ pgtable = memalign(4096, PAGETABLE_SIZE);
+ if (!pgtable)
+ return -ENOMEM;
+
+ build_pagetable(pgtable);
+ cpu_call64((ulong)pgtable, setup_base, target);
+ free(pgtable);
+
+ return -EFAULT;
+}
+
+#ifdef CONFIG_SMP
+static int enable_smis(struct udevice *cpu, void *unused)
+{
+ return 0;
+}
+
+static struct mp_flight_record mp_steps[] = {
+ MP_FR_BLOCK_APS(mp_init_cpu, NULL, mp_init_cpu, NULL),
+ /* Wait for APs to finish initialization before proceeding */
+ MP_FR_BLOCK_APS(NULL, NULL, enable_smis, NULL),
+};
+
+int x86_mp_init(void)
+{
+ struct mp_params mp_params;
+
+ mp_params.parallel_microcode_load = 0,
+ mp_params.flight_plan = &mp_steps[0];
+ mp_params.num_records = ARRAY_SIZE(mp_steps);
+ mp_params.microcode_pointer = 0;
+
+ if (mp_init(&mp_params)) {
+ printf("Warning: MP init failure\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+#endif
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