diff options
Diffstat (limited to 'arch/x86/lib/sfi.c')
-rw-r--r-- | arch/x86/lib/sfi.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/arch/x86/lib/sfi.c b/arch/x86/lib/sfi.c new file mode 100644 index 0000000000..3d3658088a --- /dev/null +++ b/arch/x86/lib/sfi.c @@ -0,0 +1,154 @@ +/* + * Copyright (c) 2015 Google, Inc + * Written by Simon Glass <sjg@chromium.org> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +/* + * Intel Simple Firmware Interface (SFI) + * + * Yet another way to pass information to the Linux kernel. + * + * See https://simplefirmware.org/ for details + */ + +#include <common.h> +#include <cpu.h> +#include <dm.h> +#include <asm/cpu.h> +#include <asm/ioapic.h> +#include <asm/sfi.h> +#include <asm/tables.h> +#include <dm/uclass-internal.h> + +struct table_info { + u32 base; + int ptr; + u32 entry_start; + u64 table[SFI_TABLE_MAX_ENTRIES]; + int count; +}; + +static void *get_entry_start(struct table_info *tab) +{ + if (tab->count == SFI_TABLE_MAX_ENTRIES) + return NULL; + tab->entry_start = tab->base + tab->ptr; + tab->table[tab->count] = tab->entry_start; + tab->entry_start += sizeof(struct sfi_table_header); + + return (void *)tab->entry_start; +} + +static void finish_table(struct table_info *tab, const char *sig, void *entry) +{ + struct sfi_table_header *hdr; + + hdr = (struct sfi_table_header *)(tab->base + tab->ptr); + strcpy(hdr->sig, sig); + hdr->len = sizeof(*hdr) + ((ulong)entry - tab->entry_start); + hdr->rev = 1; + strncpy(hdr->oem_id, "U-Boot", SFI_OEM_ID_SIZE); + strncpy(hdr->oem_table_id, "Table v1", SFI_OEM_TABLE_ID_SIZE); + hdr->csum = 0; + hdr->csum = table_compute_checksum(hdr, hdr->len); + tab->ptr += hdr->len; + tab->ptr = ALIGN(tab->ptr, 16); + tab->count++; +} + +static int sfi_write_system_header(struct table_info *tab) +{ + u64 *entry = get_entry_start(tab); + int i; + + if (!entry) + return -ENOSPC; + + for (i = 0; i < tab->count; i++) + *entry++ = tab->table[i]; + finish_table(tab, SFI_SIG_SYST, entry); + + return 0; +} + +static int sfi_write_cpus(struct table_info *tab) +{ + struct sfi_cpu_table_entry *entry = get_entry_start(tab); + struct udevice *dev; + int count = 0; + + if (!entry) + return -ENOSPC; + + for (uclass_find_first_device(UCLASS_CPU, &dev); + dev; + uclass_find_next_device(&dev)) { + struct cpu_platdata *plat = dev_get_parent_platdata(dev); + + if (!device_active(dev)) + continue; + entry->apic_id = plat->cpu_id; + entry++; + count++; + } + + /* Omit the table if there is only one CPU */ + if (count > 1) + finish_table(tab, SFI_SIG_CPUS, entry); + + return 0; +} + +static int sfi_write_apic(struct table_info *tab) +{ + struct sfi_apic_table_entry *entry = get_entry_start(tab); + + if (!entry) + return -ENOSPC; + + entry->phys_addr = IO_APIC_ADDR; + entry++; + finish_table(tab, SFI_SIG_APIC, entry); + + return 0; +} + +static int sfi_write_xsdt(struct table_info *tab) +{ + struct sfi_xsdt_header *entry = get_entry_start(tab); + + if (!entry) + return -ENOSPC; + + entry->oem_revision = 1; + entry->creator_id = 1; + entry->creator_revision = 1; + entry++; + finish_table(tab, SFI_SIG_XSDT, entry); + + return 0; +} + +u32 write_sfi_table(u32 base) +{ + struct table_info table; + + table.base = base; + table.ptr = 0; + table.count = 0; + sfi_write_cpus(&table); + sfi_write_apic(&table); + + /* + * The SFI specification marks the XSDT table as option, but Linux 4.0 + * crashes on start-up when it is not provided. + */ + sfi_write_xsdt(&table); + + /* Finally, write out the system header which points to the others */ + sfi_write_system_header(&table); + + return base + table.ptr; +} |