1 files changed, 379 insertions, 0 deletions

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
new file mode 100644
index 000000000000..263591afd29e
--- /dev/null
+++ b/arch/x86/kernel/tboot.c
@@ -0,0 +1,379 @@
+/*
+ * tboot.c: main implementation of helper functions used by kernel for
+ *          runtime support of Intel(R) Trusted Execution Technology
+ *
+ * Copyright (c) 2006-2009, Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <linux/dma_remapping.h>
+#include <linux/init_task.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/dmar.h>
+#include <linux/pfn.h>
+#include <linux/mm.h>
+
+#include <asm/trampoline.h>
+#include <asm/processor.h>
+#include <asm/bootparam.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/setup.h>
+#include <asm/tboot.h>
+#include <asm/e820.h>
+#include <asm/io.h>
+
+#include "acpi/realmode/wakeup.h"
+
+/* Global pointer to shared data; NULL means no measured launch. */
+struct tboot *tboot __read_mostly;
+
+/* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */
+#define AP_WAIT_TIMEOUT         1
+
+#undef pr_fmt
+#define pr_fmt(fmt)     "tboot: " fmt
+
+static u8 tboot_uuid[16] __initdata = TBOOT_UUID;
+
+void __init tboot_probe(void)
+{
+        /* Look for valid page-aligned address for shared page. */
+        if (!boot_params.tboot_addr)
+                return;
+        /*
+         * also verify that it is mapped as we expect it before calling
+         * set_fixmap(), to reduce chance of garbage value causing crash
+         */
+        if (!e820_any_mapped(boot_params.tboot_addr,
+                             boot_params.tboot_addr, E820_RESERVED)) {
+                pr_warning("non-0 tboot_addr but it is not of type E820_RESERVED\n");
+                return;
+        }
+
+        /* only a natively booted kernel should be using TXT */
+        if (paravirt_enabled()) {
+                pr_warning("non-0 tboot_addr but pv_ops is enabled\n");
+                return;
+        }
+
+        /* Map and check for tboot UUID. */
+        set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr);
+        tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE);
+        if (memcmp(&tboot_uuid, &tboot->uuid, sizeof(tboot->uuid))) {
+                pr_warning("tboot at 0x%llx is invalid\n",
+                           boot_params.tboot_addr);
+                tboot = NULL;
+                return;
+        }
+        if (tboot->version < 5) {
+                pr_warning("tboot version is invalid: %u\n", tboot->version);
+                tboot = NULL;
+                return;
+        }
+
+        pr_info("found shared page at phys addr 0x%llx:\n",
+                boot_params.tboot_addr);
+        pr_debug("version: %d\n", tboot->version);
+        pr_debug("log_addr: 0x%08x\n", tboot->log_addr);
+        pr_debug("shutdown_entry: 0x%x\n", tboot->shutdown_entry);
+        pr_debug("tboot_base: 0x%08x\n", tboot->tboot_base);
+        pr_debug("tboot_size: 0x%x\n", tboot->tboot_size);
+}
+
+static pgd_t *tboot_pg_dir;
+static struct mm_struct tboot_mm = {
+        .mm_rb          = RB_ROOT,
+        .pgd            = swapper_pg_dir,
+        .mm_users       = ATOMIC_INIT(2),
+        .mm_count       = ATOMIC_INIT(1),
+        .mmap_sem       = __RWSEM_INITIALIZER(init_mm.mmap_sem),
+        .page_table_lock =  __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
+        .mmlist         = LIST_HEAD_INIT(init_mm.mmlist),
+        .cpu_vm_mask    = CPU_MASK_ALL,
+};
+
+static inline void switch_to_tboot_pt(void)
+{
+        write_cr3(virt_to_phys(tboot_pg_dir));
+}
+
+static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
+                          pgprot_t prot)
+{
+        pgd_t *pgd;
+        pud_t *pud;
+        pmd_t *pmd;
+        pte_t *pte;
+
+        pgd = pgd_offset(&tboot_mm, vaddr);
+        pud = pud_alloc(&tboot_mm, pgd, vaddr);
+        if (!pud)
+                return -1;
+        pmd = pmd_alloc(&tboot_mm, pud, vaddr);
+        if (!pmd)
+                return -1;
+        pte = pte_alloc_map(&tboot_mm, pmd, vaddr);
+        if (!pte)
+                return -1;
+        set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
+        pte_unmap(pte);
+        return 0;
+}
+
+static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn,
+                           unsigned long nr)
+{
+        /* Reuse the original kernel mapping */
+        tboot_pg_dir = pgd_alloc(&tboot_mm);
+        if (!tboot_pg_dir)
+                return -1;
+
+        for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) {
+                if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC))
+                        return -1;
+        }
+
+        return 0;
+}
+
+void tboot_create_trampoline(void)
+{
+        u32 map_base, map_size;
+
+        if (!tboot_enabled())
+                return;
+
+        /* Create identity map for tboot shutdown code. */
+        map_base = PFN_DOWN(tboot->tboot_base);
+        map_size = PFN_UP(tboot->tboot_size);
+        if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size))
+                panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n", map_base, map_size);
+}
+
+static void set_mac_regions(void)
+{
+        tboot->num_mac_regions = 3;
+        /* S3 resume code */
+        tboot->mac_regions[0].start = PFN_PHYS(PFN_DOWN(acpi_wakeup_address));
+        tboot->mac_regions[0].size = PFN_UP(WAKEUP_SIZE) << PAGE_SHIFT;
+        /* AP trampoline code */
+        tboot->mac_regions[1].start =
+                        PFN_PHYS(PFN_DOWN(virt_to_phys(trampoline_base)));
+        tboot->mac_regions[1].size = PFN_UP(TRAMPOLINE_SIZE) << PAGE_SHIFT;
+        /* kernel code + data + bss */
+        tboot->mac_regions[2].start = PFN_PHYS(PFN_DOWN(virt_to_phys(&_text)));
+        tboot->mac_regions[2].size = PFN_PHYS(PFN_UP(virt_to_phys(&_end))) -
+                                     PFN_PHYS(PFN_DOWN(virt_to_phys(&_text)));
+}
+
+void tboot_shutdown(u32 shutdown_type)
+{
+        void (*shutdown)(void);
+
+        if (!tboot_enabled())
+                return;
+
+        /*
+         * if we're being called before the 1:1 mapping is set up then just
+         * return and let the normal shutdown happen; this should only be
+         * due to very early panic()
+         */
+        if (!tboot_pg_dir)
+                return;
+
+        /* if this is S3 then set regions to MAC */
+        if (shutdown_type == TB_SHUTDOWN_S3)
+                set_mac_regions();
+
+        tboot->shutdown_type = shutdown_type;
+
+        switch_to_tboot_pt();
+
+        shutdown = (void(*)(void))(unsigned long)tboot->shutdown_entry;
+        shutdown();
+
+        /* should not reach here */
+        while (1)
+                halt();
+}
+
+static void tboot_copy_fadt(const struct acpi_table_fadt *fadt)
+{
+#define TB_COPY_GAS(tbg, g)                     \
+        tbg.space_id     = g.space_id;          \
+        tbg.bit_width    = g.bit_width;         \
+        tbg.bit_offset   = g.bit_offset;        \
+        tbg.access_width = g.access_width;      \
+        tbg.address      = g.address;
+
+        TB_COPY_GAS(tboot->acpi_sinfo.pm1a_cnt_blk, fadt->xpm1a_control_block);
+        TB_COPY_GAS(tboot->acpi_sinfo.pm1b_cnt_blk, fadt->xpm1b_control_block);
+        TB_COPY_GAS(tboot->acpi_sinfo.pm1a_evt_blk, fadt->xpm1a_event_block);
+        TB_COPY_GAS(tboot->acpi_sinfo.pm1b_evt_blk, fadt->xpm1b_event_block);
+
+        /*
+         * We need phys addr of waking vector, but can't use virt_to_phys() on
+         * &acpi_gbl_FACS because it is ioremap'ed, so calc from FACS phys
+         * addr.
+         */
+        tboot->acpi_sinfo.wakeup_vector = fadt->facs +
+                offsetof(struct acpi_table_facs, firmware_waking_vector);
+}
+
+void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
+{
+        static u32 acpi_shutdown_map[ACPI_S_STATE_COUNT] = {
+                /* S0,1,2: */ -1, -1, -1,
+                /* S3: */ TB_SHUTDOWN_S3,
+                /* S4: */ TB_SHUTDOWN_S4,
+                /* S5: */ TB_SHUTDOWN_S5 };
+
+        if (!tboot_enabled())
+                return;
+
+        tboot_copy_fadt(&acpi_gbl_FADT);
+        tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control;
+        tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control;
+        /* we always use the 32b wakeup vector */
+        tboot->acpi_sinfo.vector_width = 32;
+        tboot->acpi_sinfo.kernel_s3_resume_vector = acpi_wakeup_address;
+
+        if (sleep_state >= ACPI_S_STATE_COUNT ||
+            acpi_shutdown_map[sleep_state] == -1) {
+                pr_warning("unsupported sleep state 0x%x\n", sleep_state);
+                return;
+        }
+
+        tboot_shutdown(acpi_shutdown_map[sleep_state]);
+}
+
+int tboot_wait_for_aps(int num_aps)
+{
+        unsigned long timeout;
+
+        if (!tboot_enabled())
+                return 0;
+
+        timeout = jiffies + AP_WAIT_TIMEOUT*HZ;
+        while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps &&
+               time_before(jiffies, timeout))
+                cpu_relax();
+
+        return time_before(jiffies, timeout) ? 0 : 1;
+}
+
+/*
+ * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE)
+ */
+
+#define TXT_PUB_CONFIG_REGS_BASE       0xfed30000
+#define TXT_PRIV_CONFIG_REGS_BASE      0xfed20000
+
+/* # pages for each config regs space - used by fixmap */
+#define NR_TXT_CONFIG_PAGES     ((TXT_PUB_CONFIG_REGS_BASE -                \
+                                  TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT)
+
+/* offsets from pub/priv config space */
+#define TXTCR_HEAP_BASE             0x0300
+#define TXTCR_HEAP_SIZE             0x0308
+
+#define SHA1_SIZE      20
+
+struct sha1_hash {
+        u8 hash[SHA1_SIZE];
+};
+
+struct sinit_mle_data {
+        u32               version;             /* currently 6 */
+        struct sha1_hash  bios_acm_id;
+        u32               edx_senter_flags;
+        u64               mseg_valid;
+        struct sha1_hash  sinit_hash;
+        struct sha1_hash  mle_hash;
+        struct sha1_hash  stm_hash;
+        struct sha1_hash  lcp_policy_hash;
+        u32               lcp_policy_control;
+        u32               rlp_wakeup_addr;
+        u32               reserved;
+        u32               num_mdrs;
+        u32               mdrs_off;
+        u32               num_vtd_dmars;
+        u32               vtd_dmars_off;
+} __packed;
+
+struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
+{
+        void *heap_base, *heap_ptr, *config;
+
+        if (!tboot_enabled())
+                return dmar_tbl;
+
+        /*
+         * ACPI tables may not be DMA protected by tboot, so use DMAR copy
+         * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
+         */
+
+        /* map config space in order to get heap addr */
+        config = ioremap(TXT_PUB_CONFIG_REGS_BASE, NR_TXT_CONFIG_PAGES *
+                         PAGE_SIZE);
+        if (!config)
+                return NULL;
+
+        /* now map TXT heap */
+        heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
+                            *(u64 *)(config + TXTCR_HEAP_SIZE));
+        iounmap(config);
+        if (!heap_base)
+                return NULL;
+
+        /* walk heap to SinitMleData */
+        /* skip BiosData */
+        heap_ptr = heap_base + *(u64 *)heap_base;
+        /* skip OsMleData */
+        heap_ptr += *(u64 *)heap_ptr;
+        /* skip OsSinitData */
+        heap_ptr += *(u64 *)heap_ptr;
+        /* now points to SinitMleDataSize; set to SinitMleData */
+        heap_ptr += sizeof(u64);
+        /* get addr of DMAR table */
+        dmar_tbl = (struct acpi_table_header *)(heap_ptr +
+                   ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
+                   sizeof(u64));
+
+        /* don't unmap heap because dmar.c needs access to this */
+
+        return dmar_tbl;
+}
+
+int tboot_force_iommu(void)
+{
+        if (!tboot_enabled())
+                return 0;
+
+        if (no_iommu || swiotlb || dmar_disabled)
+                pr_warning("Forcing Intel-IOMMU to enabled\n");
+
+        dmar_disabled = 0;
+#ifdef CONFIG_SWIOTLB
+        swiotlb = 0;
+#endif
+        no_iommu = 0;
+
+        return 1;
+}