By providing a proper ioremap function, we can just rely on devices
calling it for each region they need (as they already do) instead of
mapping a big assumed I/O range. We don't require the MMU to be
enabled at the time of the ioremap. In that case, we add the mapping
to the identity map anyway. This allows us to call setup_vm after
io_init. Why don't we just call setup_vm before io_init, I hear you
ask? Well, that's because tests like sieve want to start with the MMU
off, later call setup_vm, and all the while have working I/O. Some
unit tests are just really demanding...
While at it, ensure we map the I/O regions with XN (execute never),
as suggested by Alexandru Elisei.
Reviewed-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
Tested-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx>
---
lib/arm/asm/io.h | 6 ++++++
lib/arm/asm/mmu.h | 3 +++
lib/arm/asm/page.h | 2 ++
lib/arm/asm/pgtable-hwdef.h | 1 +
lib/arm/mmu.c | 37 +++++++++++++++++++++++++++----------
lib/arm64/asm/io.h | 6 ++++++
lib/arm64/asm/mmu.h | 1 +
lib/arm64/asm/page.h | 2 ++
8 files changed, 48 insertions(+), 10 deletions(-)
diff --git a/lib/arm/asm/io.h b/lib/arm/asm/io.h
index ba3b0b2412ad..e4caa6ff5d1e 100644
--- a/lib/arm/asm/io.h
+++ b/lib/arm/asm/io.h
@@ -77,6 +77,12 @@ static inline void __raw_writel(u32 val, volatile void __iomem *addr)
: "r" (val));
}
+#define ioremap ioremap
+static inline void __iomem *ioremap(phys_addr_t phys_addr, size_t size)
+{
+ return __ioremap(phys_addr, size);
+}
+
#define virt_to_phys virt_to_phys
static inline phys_addr_t virt_to_phys(const volatile void *x)
{
diff --git a/lib/arm/asm/mmu.h b/lib/arm/asm/mmu.h
index 122874b8aebe..94e70f0a84bf 100644
--- a/lib/arm/asm/mmu.h
+++ b/lib/arm/asm/mmu.h
@@ -8,10 +8,13 @@
#include <asm/barrier.h>
#define PTE_USER L_PTE_USER
+#define PTE_UXN L_PTE_XN
+#define PTE_PXN L_PTE_PXN
#define PTE_RDONLY PTE_AP2
#define PTE_SHARED L_PTE_SHARED
#define PTE_AF PTE_EXT_AF
#define PTE_WBWA L_PTE_MT_WRITEALLOC
+#define PTE_UNCACHED L_PTE_MT_UNCACHED
/* See B3.18.7 TLB maintenance operations */
diff --git a/lib/arm/asm/page.h b/lib/arm/asm/page.h
index 1fb5cd26ac66..8eb4a883808e 100644
--- a/lib/arm/asm/page.h
+++ b/lib/arm/asm/page.h
@@ -47,5 +47,7 @@ typedef struct { pteval_t pgprot; } pgprot_t;
extern phys_addr_t __virt_to_phys(unsigned long addr);
extern unsigned long __phys_to_virt(phys_addr_t addr);
+extern void *__ioremap(phys_addr_t phys_addr, size_t size);
+
#endif /* !__ASSEMBLY__ */
#endif /* _ASMARM_PAGE_H_ */
diff --git a/lib/arm/asm/pgtable-hwdef.h b/lib/arm/asm/pgtable-hwdef.h
index fe1d8540ea3f..90fd306c7cc0 100644
--- a/lib/arm/asm/pgtable-hwdef.h
+++ b/lib/arm/asm/pgtable-hwdef.h
@@ -34,6 +34,7 @@
#define L_PTE_USER (_AT(pteval_t, 1) << 6) /* AP[1] */
#define L_PTE_SHARED (_AT(pteval_t, 3) << 8) /* SH[1:0], inner shareable */
#define L_PTE_YOUNG (_AT(pteval_t, 1) << 10) /* AF */
+#define L_PTE_PXN (_AT(pteval_t, 1) << 53) /* PXN */
#define L_PTE_XN (_AT(pteval_t, 1) << 54) /* XN */
/*
diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c
index 15eef007f256..791b1f88f946 100644
--- a/lib/arm/mmu.c
+++ b/lib/arm/mmu.c
@@ -11,6 +11,7 @@
#include <asm/mmu.h>
#include <asm/setup.h>
#include <asm/page.h>
+#include <asm/io.h>
#include "alloc_page.h"
#include "vmalloc.h"
@@ -157,9 +158,8 @@ void mmu_set_range_sect(pgd_t *pgtable, uintptr_t virt_offset,
void *setup_mmu(phys_addr_t phys_end)
{
uintptr_t code_end = (uintptr_t)&etext;
- struct mem_region *r;
- /* 0G-1G = I/O, 1G-3G = identity, 3G-4G = vmalloc */
+ /* 3G-4G region is reserved for vmalloc, cap phys_end at 3G */
if (phys_end > (3ul << 30))
phys_end = 3ul << 30;
@@ -170,14 +170,8 @@ void *setup_mmu(phys_addr_t phys_end)
"Unsupported translation granule %ld\n", PAGE_SIZE);
#endif
- mmu_idmap = alloc_page();
-
- for (r = mem_regions; r->end; ++r) {
- if (!(r->flags & MR_F_IO))
- continue;
- mmu_set_range_sect(mmu_idmap, r->start, r->start, r->end,
- __pgprot(PMD_SECT_UNCACHED | PMD_SECT_USER));
- }
+ if (!mmu_idmap)
+ mmu_idmap = alloc_page();
/* armv8 requires code shared between EL1 and EL0 to be read-only */
mmu_set_range_ptes(mmu_idmap, PHYS_OFFSET,
@@ -192,6 +186,29 @@ void *setup_mmu(phys_addr_t phys_end)
return mmu_idmap;
}
+void __iomem *__ioremap(phys_addr_t phys_addr, size_t size)
+{
+ phys_addr_t paddr_aligned = phys_addr & PAGE_MASK;
+ phys_addr_t paddr_end = PAGE_ALIGN(phys_addr + size);
+ pgprot_t prot = __pgprot(PTE_UNCACHED | PTE_USER | PTE_UXN | PTE_PXN);
+ pgd_t *pgtable;
+
+ assert(sizeof(long) == 8 || !(phys_addr >> 32));
+
+ if (mmu_enabled()) {
+ pgtable = current_thread_info()->pgtable;
+ } else {
+ if (!mmu_idmap)
+ mmu_idmap = alloc_page();
+ pgtable = mmu_idmap;
+ }
+
+ mmu_set_range_ptes(pgtable, paddr_aligned, paddr_aligned,
+ paddr_end, prot);
+
+ return (void __iomem *)(unsigned long)phys_addr;
+}
+
phys_addr_t __virt_to_phys(unsigned long addr)
{
if (mmu_enabled()) {
diff --git a/lib/arm64/asm/io.h b/lib/arm64/asm/io.h
index e0a03b250d5b..be19f471c0fa 100644
--- a/lib/arm64/asm/io.h
+++ b/lib/arm64/asm/io.h
@@ -71,6 +71,12 @@ static inline u64 __raw_readq(const volatile void __iomem *addr)
return val;
}
+#define ioremap ioremap
+static inline void __iomem *ioremap(phys_addr_t phys_addr, size_t size)
+{
+ return __ioremap(phys_addr, size);
+}
+
#define virt_to_phys virt_to_phys
static inline phys_addr_t virt_to_phys(const volatile void *x)
{
diff --git a/lib/arm64/asm/mmu.h b/lib/arm64/asm/mmu.h
index 72d75eafc882..72371b2d9fe3 100644
--- a/lib/arm64/asm/mmu.h
+++ b/lib/arm64/asm/mmu.h
@@ -8,6 +8,7 @@
#include <asm/barrier.h>
#define PMD_SECT_UNCACHED PMD_ATTRINDX(MT_DEVICE_nGnRE)
+#define PTE_UNCACHED PTE_ATTRINDX(MT_DEVICE_nGnRE)
#define PTE_WBWA PTE_ATTRINDX(MT_NORMAL)
static inline void flush_tlb_all(void)
diff --git a/lib/arm64/asm/page.h b/lib/arm64/asm/page.h
index ae4484b22114..d0fac6ea563d 100644
--- a/lib/arm64/asm/page.h
+++ b/lib/arm64/asm/page.h
@@ -72,5 +72,7 @@ typedef struct { pteval_t pgprot; } pgprot_t;
extern phys_addr_t __virt_to_phys(unsigned long addr);
extern unsigned long __phys_to_virt(phys_addr_t addr);
+extern void *__ioremap(phys_addr_t phys_addr, size_t size);
+
#endif /* !__ASSEMBLY__ */
#endif /* _ASMARM64_PAGE_H_ */
--
2.30.2
