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authorLinus Torvalds <torvalds@linux-foundation.org>2017-02-22 21:46:44 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-22 21:46:44 +0300
commitca78d3173cff3503bcd15723b049757f75762d15 (patch)
tree8e5db7a3adbe3bcd3b08e6983a6e0f6becb0aaa0 /arch/arm64/mm
parenta4ee7bacd6c08479d56738456c07e4f32fc8e523 (diff)
parentffe7afd1713558d73483834c2e2d03a1e39a4062 (diff)
downloadlinux-ca78d3173cff3503bcd15723b049757f75762d15.tar.xz
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon: - Errata workarounds for Qualcomm's Falkor CPU - Qualcomm L2 Cache PMU driver - Qualcomm SMCCC firmware quirk - Support for DEBUG_VIRTUAL - CPU feature detection for userspace via MRS emulation - Preliminary work for the Statistical Profiling Extension - Misc cleanups and non-critical fixes * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (74 commits) arm64/kprobes: consistently handle MRS/MSR with XZR arm64: cpufeature: correctly handle MRS to XZR arm64: traps: correctly handle MRS/MSR with XZR arm64: ptrace: add XZR-safe regs accessors arm64: include asm/assembler.h in entry-ftrace.S arm64: fix warning about swapper_pg_dir overflow arm64: Work around Falkor erratum 1003 arm64: head.S: Enable EL1 (host) access to SPE when entered at EL2 arm64: arch_timer: document Hisilicon erratum 161010101 arm64: use is_vmalloc_addr arm64: use linux/sizes.h for constants arm64: uaccess: consistently check object sizes perf: add qcom l2 cache perf events driver arm64: remove wrong CONFIG_PROC_SYSCTL ifdef ARM: smccc: Update HVC comment to describe new quirk parameter arm64: do not trace atomic operations ACPI/IORT: Fix the error return code in iort_add_smmu_platform_device() ACPI/IORT: Fix iort_node_get_id() mapping entries indexing arm64: mm: enable CONFIG_HOLES_IN_ZONE for NUMA perf: xgene: Include module.h ...
Diffstat (limited to 'arch/arm64/mm')
-rw-r--r--arch/arm64/mm/Makefile2
-rw-r--r--arch/arm64/mm/context.c11
-rw-r--r--arch/arm64/mm/dma-mapping.c38
-rw-r--r--arch/arm64/mm/fault.c14
-rw-r--r--arch/arm64/mm/init.c12
-rw-r--r--arch/arm64/mm/ioremap.c2
-rw-r--r--arch/arm64/mm/kasan_init.c22
-rw-r--r--arch/arm64/mm/mmu.c35
-rw-r--r--arch/arm64/mm/physaddr.c30
-rw-r--r--arch/arm64/mm/proc.S1
10 files changed, 117 insertions, 50 deletions
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile
index e703fb9defad..9b0ba191e48e 100644
--- a/arch/arm64/mm/Makefile
+++ b/arch/arm64/mm/Makefile
@@ -6,6 +6,8 @@ obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_ARM64_PTDUMP_CORE) += dump.o
obj-$(CONFIG_ARM64_PTDUMP_DEBUGFS) += ptdump_debugfs.o
obj-$(CONFIG_NUMA) += numa.o
+obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o
+KASAN_SANITIZE_physaddr.o += n
obj-$(CONFIG_KASAN) += kasan_init.o
KASAN_SANITIZE_kasan_init.o := n
diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c
index 4c63cb154859..68634c630cdd 100644
--- a/arch/arm64/mm/context.c
+++ b/arch/arm64/mm/context.c
@@ -79,6 +79,13 @@ void verify_cpu_asid_bits(void)
}
}
+static void set_reserved_asid_bits(void)
+{
+ if (IS_ENABLED(CONFIG_QCOM_FALKOR_ERRATUM_1003) &&
+ cpus_have_const_cap(ARM64_WORKAROUND_QCOM_FALKOR_E1003))
+ __set_bit(FALKOR_RESERVED_ASID, asid_map);
+}
+
static void flush_context(unsigned int cpu)
{
int i;
@@ -87,6 +94,8 @@ static void flush_context(unsigned int cpu)
/* Update the list of reserved ASIDs and the ASID bitmap. */
bitmap_clear(asid_map, 0, NUM_USER_ASIDS);
+ set_reserved_asid_bits();
+
/*
* Ensure the generation bump is observed before we xchg the
* active_asids.
@@ -244,6 +253,8 @@ static int asids_init(void)
panic("Failed to allocate bitmap for %lu ASIDs\n",
NUM_USER_ASIDS);
+ set_reserved_asid_bits();
+
pr_info("ASID allocator initialised with %lu entries\n", NUM_USER_ASIDS);
return 0;
}
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 4a14b25163fb..351f7595cb3e 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -211,7 +211,8 @@ static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
dma_addr_t dev_addr;
dev_addr = swiotlb_map_page(dev, page, offset, size, dir, attrs);
- if (!is_device_dma_coherent(dev))
+ if (!is_device_dma_coherent(dev) &&
+ (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
return dev_addr;
@@ -222,7 +223,8 @@ static void __swiotlb_unmap_page(struct device *dev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir,
unsigned long attrs)
{
- if (!is_device_dma_coherent(dev))
+ if (!is_device_dma_coherent(dev) &&
+ (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
swiotlb_unmap_page(dev, dev_addr, size, dir, attrs);
}
@@ -235,7 +237,8 @@ static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
int i, ret;
ret = swiotlb_map_sg_attrs(dev, sgl, nelems, dir, attrs);
- if (!is_device_dma_coherent(dev))
+ if (!is_device_dma_coherent(dev) &&
+ (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
for_each_sg(sgl, sg, ret, i)
__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
sg->length, dir);
@@ -251,7 +254,8 @@ static void __swiotlb_unmap_sg_attrs(struct device *dev,
struct scatterlist *sg;
int i;
- if (!is_device_dma_coherent(dev))
+ if (!is_device_dma_coherent(dev) &&
+ (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
for_each_sg(sgl, sg, nelems, i)
__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
sg->length, dir);
@@ -352,6 +356,13 @@ static int __swiotlb_dma_supported(struct device *hwdev, u64 mask)
return 1;
}
+static int __swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t addr)
+{
+ if (swiotlb)
+ return swiotlb_dma_mapping_error(hwdev, addr);
+ return 0;
+}
+
static struct dma_map_ops swiotlb_dma_ops = {
.alloc = __dma_alloc,
.free = __dma_free,
@@ -366,7 +377,7 @@ static struct dma_map_ops swiotlb_dma_ops = {
.sync_sg_for_cpu = __swiotlb_sync_sg_for_cpu,
.sync_sg_for_device = __swiotlb_sync_sg_for_device,
.dma_supported = __swiotlb_dma_supported,
- .mapping_error = swiotlb_dma_mapping_error,
+ .mapping_error = __swiotlb_dma_mapping_error,
};
static int __init atomic_pool_init(void)
@@ -830,14 +841,21 @@ static bool do_iommu_attach(struct device *dev, const struct iommu_ops *ops,
* then the IOMMU core will have already configured a group for this
* device, and allocated the default domain for that group.
*/
- if (!domain || iommu_dma_init_domain(domain, dma_base, size, dev)) {
- pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",
- dev_name(dev));
- return false;
+ if (!domain)
+ goto out_err;
+
+ if (domain->type == IOMMU_DOMAIN_DMA) {
+ if (iommu_dma_init_domain(domain, dma_base, size, dev))
+ goto out_err;
+
+ dev->archdata.dma_ops = &iommu_dma_ops;
}
- dev->archdata.dma_ops = &iommu_dma_ops;
return true;
+out_err:
+ pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",
+ dev_name(dev));
+ return false;
}
static void queue_iommu_attach(struct device *dev, const struct iommu_ops *ops,
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 156169c6981b..81283851c9af 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -691,17 +691,3 @@ int cpu_enable_pan(void *__unused)
return 0;
}
#endif /* CONFIG_ARM64_PAN */
-
-#ifdef CONFIG_ARM64_UAO
-/*
- * Kernel threads have fs=KERNEL_DS by default, and don't need to call
- * set_fs(), devtmpfs in particular relies on this behaviour.
- * We need to enable the feature at runtime (instead of adding it to
- * PSR_MODE_EL1h) as the feature may not be implemented by the cpu.
- */
-int cpu_enable_uao(void *__unused)
-{
- asm(SET_PSTATE_UAO(1));
- return 0;
-}
-#endif /* CONFIG_ARM64_UAO */
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 380ebe705093..e19e06593e37 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -36,6 +36,7 @@
#include <linux/efi.h>
#include <linux/swiotlb.h>
#include <linux/vmalloc.h>
+#include <linux/mm.h>
#include <asm/boot.h>
#include <asm/fixmap.h>
@@ -209,8 +210,8 @@ void __init arm64_memblock_init(void)
* linear mapping. Take care not to clip the kernel which may be
* high in memory.
*/
- memblock_remove(max_t(u64, memstart_addr + linear_region_size, __pa(_end)),
- ULLONG_MAX);
+ memblock_remove(max_t(u64, memstart_addr + linear_region_size,
+ __pa_symbol(_end)), ULLONG_MAX);
if (memstart_addr + linear_region_size < memblock_end_of_DRAM()) {
/* ensure that memstart_addr remains sufficiently aligned */
memstart_addr = round_up(memblock_end_of_DRAM() - linear_region_size,
@@ -225,7 +226,7 @@ void __init arm64_memblock_init(void)
*/
if (memory_limit != (phys_addr_t)ULLONG_MAX) {
memblock_mem_limit_remove_map(memory_limit);
- memblock_add(__pa(_text), (u64)(_end - _text));
+ memblock_add(__pa_symbol(_text), (u64)(_end - _text));
}
if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_start) {
@@ -278,7 +279,7 @@ void __init arm64_memblock_init(void)
* Register the kernel text, kernel data, initrd, and initial
* pagetables with memblock.
*/
- memblock_reserve(__pa(_text), _end - _text);
+ memblock_reserve(__pa_symbol(_text), _end - _text);
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_start) {
memblock_reserve(initrd_start, initrd_end - initrd_start);
@@ -486,7 +487,8 @@ void __init mem_init(void)
void free_initmem(void)
{
- free_reserved_area(__va(__pa(__init_begin)), __va(__pa(__init_end)),
+ free_reserved_area(lm_alias(__init_begin),
+ lm_alias(__init_end),
0, "unused kernel");
/*
* Unmap the __init region but leave the VM area in place. This
diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c
index 01e88c8bcab0..c4c8cd4c31d4 100644
--- a/arch/arm64/mm/ioremap.c
+++ b/arch/arm64/mm/ioremap.c
@@ -88,7 +88,7 @@ void __iounmap(volatile void __iomem *io_addr)
* We could get an address outside vmalloc range in case
* of ioremap_cache() reusing a RAM mapping.
*/
- if (VMALLOC_START <= addr && addr < VMALLOC_END)
+ if (is_vmalloc_addr((void *)addr))
vunmap((void *)addr);
}
EXPORT_SYMBOL(__iounmap);
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index 757009daa9ed..201d918e7575 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -15,6 +15,7 @@
#include <linux/kernel.h>
#include <linux/memblock.h>
#include <linux/start_kernel.h>
+#include <linux/mm.h>
#include <asm/mmu_context.h>
#include <asm/kernel-pgtable.h>
@@ -26,6 +27,13 @@
static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE);
+/*
+ * The p*d_populate functions call virt_to_phys implicitly so they can't be used
+ * directly on kernel symbols (bm_p*d). All the early functions are called too
+ * early to use lm_alias so __p*d_populate functions must be used to populate
+ * with the physical address from __pa_symbol.
+ */
+
static void __init kasan_early_pte_populate(pmd_t *pmd, unsigned long addr,
unsigned long end)
{
@@ -33,12 +41,12 @@ static void __init kasan_early_pte_populate(pmd_t *pmd, unsigned long addr,
unsigned long next;
if (pmd_none(*pmd))
- pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
+ __pmd_populate(pmd, __pa_symbol(kasan_zero_pte), PMD_TYPE_TABLE);
pte = pte_offset_kimg(pmd, addr);
do {
next = addr + PAGE_SIZE;
- set_pte(pte, pfn_pte(virt_to_pfn(kasan_zero_page),
+ set_pte(pte, pfn_pte(sym_to_pfn(kasan_zero_page),
PAGE_KERNEL));
} while (pte++, addr = next, addr != end && pte_none(*pte));
}
@@ -51,7 +59,7 @@ static void __init kasan_early_pmd_populate(pud_t *pud,
unsigned long next;
if (pud_none(*pud))
- pud_populate(&init_mm, pud, kasan_zero_pmd);
+ __pud_populate(pud, __pa_symbol(kasan_zero_pmd), PMD_TYPE_TABLE);
pmd = pmd_offset_kimg(pud, addr);
do {
@@ -68,7 +76,7 @@ static void __init kasan_early_pud_populate(pgd_t *pgd,
unsigned long next;
if (pgd_none(*pgd))
- pgd_populate(&init_mm, pgd, kasan_zero_pud);
+ __pgd_populate(pgd, __pa_symbol(kasan_zero_pud), PUD_TYPE_TABLE);
pud = pud_offset_kimg(pgd, addr);
do {
@@ -148,7 +156,7 @@ void __init kasan_init(void)
*/
memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(tmp_pg_dir));
dsb(ishst);
- cpu_replace_ttbr1(tmp_pg_dir);
+ cpu_replace_ttbr1(lm_alias(tmp_pg_dir));
clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
@@ -199,10 +207,10 @@ void __init kasan_init(void)
*/
for (i = 0; i < PTRS_PER_PTE; i++)
set_pte(&kasan_zero_pte[i],
- pfn_pte(virt_to_pfn(kasan_zero_page), PAGE_KERNEL_RO));
+ pfn_pte(sym_to_pfn(kasan_zero_page), PAGE_KERNEL_RO));
memset(kasan_zero_page, 0, PAGE_SIZE);
- cpu_replace_ttbr1(swapper_pg_dir);
+ cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
/* At this point kasan is fully initialized. Enable error messages */
init_task.kasan_depth = 0;
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 17243e43184e..b805c017f789 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -28,6 +28,7 @@
#include <linux/memblock.h>
#include <linux/fs.h>
#include <linux/io.h>
+#include <linux/mm.h>
#include <asm/barrier.h>
#include <asm/cputype.h>
@@ -359,8 +360,8 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt,
static void __init __map_memblock(pgd_t *pgd, phys_addr_t start, phys_addr_t end)
{
- unsigned long kernel_start = __pa(_text);
- unsigned long kernel_end = __pa(__init_begin);
+ phys_addr_t kernel_start = __pa_symbol(_text);
+ phys_addr_t kernel_end = __pa_symbol(__init_begin);
/*
* Take care not to create a writable alias for the
@@ -427,14 +428,14 @@ void mark_rodata_ro(void)
unsigned long section_size;
section_size = (unsigned long)_etext - (unsigned long)_text;
- create_mapping_late(__pa(_text), (unsigned long)_text,
+ create_mapping_late(__pa_symbol(_text), (unsigned long)_text,
section_size, PAGE_KERNEL_ROX);
/*
* mark .rodata as read only. Use __init_begin rather than __end_rodata
* to cover NOTES and EXCEPTION_TABLE.
*/
section_size = (unsigned long)__init_begin - (unsigned long)__start_rodata;
- create_mapping_late(__pa(__start_rodata), (unsigned long)__start_rodata,
+ create_mapping_late(__pa_symbol(__start_rodata), (unsigned long)__start_rodata,
section_size, PAGE_KERNEL_RO);
/* flush the TLBs after updating live kernel mappings */
@@ -446,7 +447,7 @@ void mark_rodata_ro(void)
static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end,
pgprot_t prot, struct vm_struct *vma)
{
- phys_addr_t pa_start = __pa(va_start);
+ phys_addr_t pa_start = __pa_symbol(va_start);
unsigned long size = va_end - va_start;
BUG_ON(!PAGE_ALIGNED(pa_start));
@@ -494,7 +495,7 @@ static void __init map_kernel(pgd_t *pgd)
*/
BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
set_pud(pud_set_fixmap_offset(pgd, FIXADDR_START),
- __pud(__pa(bm_pmd) | PUD_TYPE_TABLE));
+ __pud(__pa_symbol(bm_pmd) | PUD_TYPE_TABLE));
pud_clear_fixmap();
} else {
BUG();
@@ -524,8 +525,8 @@ void __init paging_init(void)
* To do this we need to go via a temporary pgd.
*/
cpu_replace_ttbr1(__va(pgd_phys));
- memcpy(swapper_pg_dir, pgd, PAGE_SIZE);
- cpu_replace_ttbr1(swapper_pg_dir);
+ memcpy(swapper_pg_dir, pgd, PGD_SIZE);
+ cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
pgd_clear_fixmap();
memblock_free(pgd_phys, PAGE_SIZE);
@@ -534,7 +535,7 @@ void __init paging_init(void)
* We only reuse the PGD from the swapper_pg_dir, not the pud + pmd
* allocated with it.
*/
- memblock_free(__pa(swapper_pg_dir) + PAGE_SIZE,
+ memblock_free(__pa_symbol(swapper_pg_dir) + PAGE_SIZE,
SWAPPER_DIR_SIZE - PAGE_SIZE);
}
@@ -645,6 +646,12 @@ static inline pte_t * fixmap_pte(unsigned long addr)
return &bm_pte[pte_index(addr)];
}
+/*
+ * The p*d_populate functions call virt_to_phys implicitly so they can't be used
+ * directly on kernel symbols (bm_p*d). This function is called too early to use
+ * lm_alias so __p*d_populate functions must be used to populate with the
+ * physical address from __pa_symbol.
+ */
void __init early_fixmap_init(void)
{
pgd_t *pgd;
@@ -654,7 +661,7 @@ void __init early_fixmap_init(void)
pgd = pgd_offset_k(addr);
if (CONFIG_PGTABLE_LEVELS > 3 &&
- !(pgd_none(*pgd) || pgd_page_paddr(*pgd) == __pa(bm_pud))) {
+ !(pgd_none(*pgd) || pgd_page_paddr(*pgd) == __pa_symbol(bm_pud))) {
/*
* We only end up here if the kernel mapping and the fixmap
* share the top level pgd entry, which should only happen on
@@ -663,12 +670,14 @@ void __init early_fixmap_init(void)
BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
pud = pud_offset_kimg(pgd, addr);
} else {
- pgd_populate(&init_mm, pgd, bm_pud);
+ if (pgd_none(*pgd))
+ __pgd_populate(pgd, __pa_symbol(bm_pud), PUD_TYPE_TABLE);
pud = fixmap_pud(addr);
}
- pud_populate(&init_mm, pud, bm_pmd);
+ if (pud_none(*pud))
+ __pud_populate(pud, __pa_symbol(bm_pmd), PMD_TYPE_TABLE);
pmd = fixmap_pmd(addr);
- pmd_populate_kernel(&init_mm, pmd, bm_pte);
+ __pmd_populate(pmd, __pa_symbol(bm_pte), PMD_TYPE_TABLE);
/*
* The boot-ioremap range spans multiple pmds, for which
diff --git a/arch/arm64/mm/physaddr.c b/arch/arm64/mm/physaddr.c
new file mode 100644
index 000000000000..91371daf397c
--- /dev/null
+++ b/arch/arm64/mm/physaddr.c
@@ -0,0 +1,30 @@
+#include <linux/bug.h>
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/mmdebug.h>
+#include <linux/mm.h>
+
+#include <asm/memory.h>
+
+phys_addr_t __virt_to_phys(unsigned long x)
+{
+ WARN(!__is_lm_address(x),
+ "virt_to_phys used for non-linear address: %pK (%pS)\n",
+ (void *)x,
+ (void *)x);
+
+ return __virt_to_phys_nodebug(x);
+}
+EXPORT_SYMBOL(__virt_to_phys);
+
+phys_addr_t __phys_addr_symbol(unsigned long x)
+{
+ /*
+ * This is bounds checking against the kernel image only.
+ * __pa_symbol should only be used on kernel symbol addresses.
+ */
+ VIRTUAL_BUG_ON(x < (unsigned long) KERNEL_START ||
+ x > (unsigned long) KERNEL_END);
+ return __pa_symbol_nodebug(x);
+}
+EXPORT_SYMBOL(__phys_addr_symbol);
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 32682be978e0..cd4d53d7e458 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -138,6 +138,7 @@ ENDPROC(cpu_do_resume)
* - pgd_phys - physical address of new TTB
*/
ENTRY(cpu_do_switch_mm)
+ pre_ttbr0_update_workaround x0, x1, x2
mmid x1, x1 // get mm->context.id
bfi x0, x1, #48, #16 // set the ASID
msr ttbr0_el1, x0 // set TTBR0