[RFC PATCH 5/5] ARM: NOMMU: Support PMSAv8 MPU
Vladimir Murzin
vladimir.murzin at arm.com
Wed Dec 13 09:02:07 PST 2017
ARMv8R/M architecture defines new memory protection scheme - PMSAv8
which is not compatible with PMSAv7.
Key differences to PMSAv7 are:
- Region geometry is defined by base and limit addresses
- Addresses need to be either 32 or 64 byte aligned
- No region priority due to overlapping regions are not allowed
- It is unified, i.e. no distinction between data/instruction regions
- Memory attributes are controlled via MAIR
This patch implements support for PMSAv8 MPU defined by ARMv8R/M
architecture.
Signed-off-by: Vladimir Murzin <vladimir.murzin at arm.com>
---
arch/arm/include/asm/mpu.h | 52 ++++++-
arch/arm/include/asm/v7m.h | 8 ++
arch/arm/kernel/asm-offsets.c | 2 +
arch/arm/kernel/head-nommu.S | 132 ++++++++++++++++++
arch/arm/mm/Makefile | 2 +-
arch/arm/mm/nommu.c | 6 +
arch/arm/mm/pmsa-v8.c | 307 ++++++++++++++++++++++++++++++++++++++++++
7 files changed, 505 insertions(+), 4 deletions(-)
create mode 100644 arch/arm/mm/pmsa-v8.c
diff --git a/arch/arm/include/asm/mpu.h b/arch/arm/include/asm/mpu.h
index fbde275..5e088c8 100644
--- a/arch/arm/include/asm/mpu.h
+++ b/arch/arm/include/asm/mpu.h
@@ -12,6 +12,7 @@
/* ID_MMFR0 data relevant to MPU */
#define MMFR0_PMSA (0xF << 4)
#define MMFR0_PMSAv7 (3 << 4)
+#define MMFR0_PMSAv8 (4 << 4)
/* MPU D/I Size Register fields */
#define PMSAv7_RSR_SZ 1
@@ -47,12 +48,43 @@
#define PMSAv7_AP_PL1RW_PL0R0 (0x2 << 8)
#define PMSAv7_AP_PL1RW_PL0NA (0x1 << 8)
+#define PMSAv8_BAR_XN 1
+
+#define PMSAv8_LAR_EN 1
+#define PMSAv8_LAR_IDX(n) (((n) & 0x7) << 1)
+
+
+#define PMSAv8_AP_PL1RW_PL0NA (0 << 1)
+#define PMSAv8_AP_PL1RW_PL0RW (1 << 1)
+#define PMSAv8_AP_PL1RO_PL0RO (3 << 1)
+
+#ifdef CONFIG_SMP
+#define PMSAv8_RGN_SHARED (3 << 3) // inner sharable
+#else
+#define PMSAv8_RGN_SHARED (0 << 3)
+#endif
+
+#define PMSAv8_RGN_DEVICE_nGnRnE 0
+#define PMSAv8_RGN_NORMAL 1
+
+#define PMSAv8_MAIR(attr, mt) ((attr) << ((mt) * 8))
+
+#ifdef CONFIG_CPU_V7M
+#define PMSAv8_MINALIGN 32
+#else
+#define PMSAv8_MINALIGN 64
+#endif
+
/* For minimal static MPU region configurations */
#define PMSAv7_PROBE_REGION 0
#define PMSAv7_BG_REGION 1
#define PMSAv7_RAM_REGION 2
#define PMSAv7_ROM_REGION 3
+/* Fixed for PMSAv8 only */
+#define PMSAv8_XIP_REGION 0
+#define PMSAv8_KERNEL_REGION 1
+
/* Maximum number of regions Linux is interested in */
#define MPU_MAX_REGIONS 16
@@ -63,9 +95,18 @@
struct mpu_rgn {
/* Assume same attributes for d/i-side */
- u32 drbar;
- u32 drsr;
- u32 dracr;
+ union {
+ u32 drbar; /* PMSAv7 */
+ u32 prbar; /* PMSAv8 */
+ };
+ union {
+ u32 drsr; /* PMSAv7 */
+ u32 prlar; /* PMSAv8 */
+ };
+ union {
+ u32 dracr; /* PMSAv7 */
+ u32 unused; /* not used in PMSAv8 */
+ };
};
struct mpu_rgn_info {
@@ -76,10 +117,15 @@ extern struct mpu_rgn_info mpu_rgn_info;
#ifdef CONFIG_ARM_MPU
extern void __init pmsav7_adjust_lowmem_bounds(void);
+extern void __init pmsav8_adjust_lowmem_bounds(void);
+
extern void __init pmsav7_setup(void);
+extern void __init pmsav8_setup(void);
#else
static inline void pmsav7_adjust_lowmem_bounds(void) {};
+static inline void pmsav8_adjust_lowmem_bounds(void) {};
static inline void pmsav7_setup(void) {};
+static inline void pmsav8_setup(void) {};
#endif
#endif /* __ASSEMBLY__ */
diff --git a/arch/arm/include/asm/v7m.h b/arch/arm/include/asm/v7m.h
index aba49e0..187ccf6 100644
--- a/arch/arm/include/asm/v7m.h
+++ b/arch/arm/include/asm/v7m.h
@@ -68,6 +68,14 @@
#define PMSAv7_RBAR 0x9c
#define PMSAv7_RASR 0xa0
+#define PMSAv8_RNR 0x98
+#define PMSAv8_RBAR 0x9c
+#define PMSAv8_RLAR 0xa0
+#define PMSAv8_RBAR_A(n) (PMSAv8_RBAR + 8*(n))
+#define PMSAv8_RLAR_A(n) (PMSAv8_RLAR + 8*(n))
+#define PMSAv8_MAIR0 0xc0
+#define PMSAv8_MAIR1 0xc4
+
/* Cache opeartions */
#define V7M_SCB_ICIALLU 0x250 /* I-cache invalidate all to PoU */
#define V7M_SCB_ICIMVAU 0x258 /* I-cache invalidate by MVA to PoU */
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 250a985..27c5381 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -197,6 +197,8 @@ int main(void)
DEFINE(MPU_RGN_DRBAR, offsetof(struct mpu_rgn, drbar));
DEFINE(MPU_RGN_DRSR, offsetof(struct mpu_rgn, drsr));
DEFINE(MPU_RGN_DRACR, offsetof(struct mpu_rgn, dracr));
+ DEFINE(MPU_RGN_PRBAR, offsetof(struct mpu_rgn, prbar));
+ DEFINE(MPU_RGN_PRLAR, offsetof(struct mpu_rgn, prlar));
#endif
return 0;
}
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S
index 482936a..cdc1177 100644
--- a/arch/arm/kernel/head-nommu.S
+++ b/arch/arm/kernel/head-nommu.S
@@ -132,6 +132,25 @@ M_CLASS(ldr r3, [r12, 0x50])
AR_CLASS(mrc p15, 0, r3, c0, c1, 4) @ Read ID_MMFR0
and r3, r3, #(MMFR0_PMSA) @ PMSA field
teq r3, #(MMFR0_PMSAv7) @ PMSA v7
+ beq 1f
+ teq r3, #(MMFR0_PMSAv8) @ PMSA v8
+ /*
+ * Memory region attributes for PMSAv8:
+ *
+ * n = AttrIndx[2:0]
+ * n MAIR
+ * DEVICE_nGnRnE 000 00000000
+ * NORMAL 001 11111111
+ */
+ ldreq r3, =PMSAv8_MAIR(0x00, PMSAv8_RGN_DEVICE_nGnRnE) | \
+ PMSAv8_MAIR(0xff, PMSAv8_RGN_NORMAL)
+AR_CLASS(mcreq p15, 0, r3, c10, c2, 0) @ MAIR 0
+M_CLASS(streq r3, [r12, #PMSAv8_MAIR0])
+ moveq r3, #0
+AR_CLASS(mcreq p15, 0, r3, c10, c2, 1) @ MAIR 1
+M_CLASS(streq r3, [r12, #PMSAv8_MAIR1])
+
+1:
#endif
#ifdef CONFIG_CPU_CP15
/*
@@ -235,6 +254,8 @@ M_CLASS(ldr r0, [r12, 0x50])
and r0, r0, #(MMFR0_PMSA) @ PMSA field
teq r0, #(MMFR0_PMSAv7) @ PMSA v7
beq __setup_pmsa_v7
+ teq r0, #(MMFR0_PMSAv8) @ PMSA v8
+ beq __setup_pmsa_v8
ret lr
ENDPROC(__setup_mpu)
@@ -304,6 +325,88 @@ M_CLASS(ldr r0, [r12, #MPU_TYPE])
ret lr
ENDPROC(__setup_pmsa_v7)
+ENTRY(__setup_pmsa_v8)
+ mov r0, #0
+AR_CLASS(mcr p15, 0, r0, c6, c2, 1) @ PRSEL
+M_CLASS(str r0, [r12, #PMSAv8_RNR])
+ isb
+
+#ifdef CONFIG_XIP_KERNEL
+ ldr r5, =CONFIG_XIP_PHYS_ADDR @ ROM start
+ ldr r6, =(_exiprom) @ ROM end
+ sub r6, r6, #1
+ bic r6, r6, #(PMSAv8_MINALIGN - 1)
+
+ orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED)
+ orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN)
+
+AR_CLASS(mcr p15, 0, r5, c6, c8, 0) @ PRBAR0
+AR_CLASS(mcr p15, 0, r6, c6, c8, 1) @ PRLAR0
+M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(0)])
+M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(0)])
+#endif
+
+ ldr r5, =KERNEL_START
+ ldr r6, =KERNEL_END
+ sub r6, r6, #1
+ bic r6, r6, #(PMSAv8_MINALIGN - 1)
+
+ orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED)
+ orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN)
+
+AR_CLASS(mcr p15, 0, r5, c6, c8, 4) @ PRBAR1
+AR_CLASS(mcr p15, 0, r6, c6, c8, 5) @ PRLAR1
+M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(1)])
+M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(1)])
+
+ /* Setup Background: 0x0 - min(KERNEL_START, XIP_PHYS_ADDR) */
+#ifdef CONFIG_XIP_KERNEL
+ ldr r6, =KERNEL_START
+ ldr r5, =CONFIG_XIP_PHYS_ADDR
+ cmp r6, r5
+ movcs r6, r5
+#else
+ ldr r6, =KERNEL_START
+#endif
+ cmp r6, #0
+ beq 1f
+
+ mov r5, #0
+ sub r6, r6, #1
+ bic r6, r6, #(PMSAv8_MINALIGN - 1)
+
+ orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN)
+ orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN)
+
+AR_CLASS(mcr p15, 0, r5, c6, c9, 0) @ PRBAR2
+AR_CLASS(mcr p15, 0, r6, c6, c9, 1) @ PRLAR2
+M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(2)])
+M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(2)])
+
+1:
+ /* Setup Background: max(KERNEL_END, _exiprom) - 0xffffffff */
+#ifdef CONFIG_XIP_KERNEL
+ ldr r5, =KERNEL_END
+ ldr r6, =(_exiprom)
+ cmp r5, r6
+ movcc r5, r6
+#else
+ ldr r5, =KERNEL_END
+#endif
+ mov r6, #0xffffffff
+ bic r6, r6, #(PMSAv8_MINALIGN - 1)
+
+ orr r5, r5, #(PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN)
+ orr r6, r6, #(PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN)
+
+AR_CLASS(mcr p15, 0, r5, c6, c9, 4) @ PRBAR3
+AR_CLASS(mcr p15, 0, r6, c6, c9, 5) @ PRLAR3
+M_CLASS(str r5, [r12, #PMSAv8_RBAR_A(3)])
+M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(3)])
+
+ ret lr
+ENDPROC(__setup_pmsa_v8)
+
#ifdef CONFIG_SMP
/*
* r6: pointer at mpu_rgn_info
@@ -319,6 +422,8 @@ ENTRY(__secondary_setup_mpu)
and r0, r0, #(MMFR0_PMSA) @ PMSA field
teq r0, #(MMFR0_PMSAv7) @ PMSA v7
beq __secondary_setup_pmsa_v7
+ teq r0, #(MMFR0_PMSAv8) @ PMSA v8
+ beq __secondary_setup_pmsa_v8
b __error_p
ENDPROC(__secondary_setup_mpu)
@@ -361,6 +466,33 @@ ENTRY(__secondary_setup_pmsa_v7)
ret lr
ENDPROC(__secondary_setup_pmsa_v7)
+ENTRY(__secondary_setup_pmsa_v8)
+ ldr r4, [r6, #MPU_RNG_INFO_USED]
+#ifndef CONFIG_XIP_KERNEL
+ add r4, r4, #1
+#endif
+ mov r5, #MPU_RNG_SIZE
+ add r3, r6, #MPU_RNG_INFO_RNGS
+ mla r3, r4, r5, r3
+
+1:
+ sub r3, r3, #MPU_RNG_SIZE
+ sub r4, r4, #1
+
+ mcr p15, 0, r4, c6, c2, 1 @ PRSEL
+ isb
+
+ ldr r5, [r3, #MPU_RGN_PRBAR]
+ ldr r6, [r3, #MPU_RGN_PRLAR]
+
+ mcr p15, 0, r5, c6, c3, 0 @ PRBAR
+ mcr p15, 0, r6, c6, c3, 1 @ PRLAR
+
+ cmp r4, #0
+ bgt 1b
+
+ ret lr
+ENDPROC(__secondary_setup_pmsa_v8)
#endif /* CONFIG_SMP */
#endif /* CONFIG_ARM_MPU */
#include "head-common.S"
diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index 01bcc33..9a9741c 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -10,7 +10,7 @@ obj-$(CONFIG_MMU) += fault-armv.o flush.o idmap.o ioremap.o \
ifneq ($(CONFIG_MMU),y)
obj-y += nommu.o
-obj-$(CONFIG_ARM_MPU) += pmsa-v7.o
+obj-$(CONFIG_ARM_MPU) += pmsa-v7.o pmsa-v8.o
endif
obj-$(CONFIG_ARM_PTDUMP) += dump.o
diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c
index 7534885..885b106 100644
--- a/arch/arm/mm/nommu.c
+++ b/arch/arm/mm/nommu.c
@@ -108,6 +108,9 @@ static void __init adjust_lowmem_bounds_mpu(void)
case MMFR0_PMSAv7:
pmsav7_adjust_lowmem_bounds();
break;
+ case MMFR0_PMSAv8:
+ pmsav8_adjust_lowmem_bounds();
+ break;
default:
break;
}
@@ -121,6 +124,9 @@ static void __init mpu_setup(void)
case MMFR0_PMSAv7:
pmsav7_setup();
break;
+ case MMFR0_PMSAv8:
+ pmsav8_setup();
+ break;
default:
break;
}
diff --git a/arch/arm/mm/pmsa-v8.c b/arch/arm/mm/pmsa-v8.c
new file mode 100644
index 0000000..64ae405
--- /dev/null
+++ b/arch/arm/mm/pmsa-v8.c
@@ -0,0 +1,307 @@
+/*
+ * Based on linux/arch/arm/pmsa-v7.c
+ *
+ * ARM PMSAv8 supporting functions.
+ */
+
+#include <linux/memblock.h>
+#include <linux/range.h>
+
+#include <asm/cp15.h>
+#include <asm/cputype.h>
+#include <asm/mpu.h>
+
+#include <asm/memory.h>
+#include <asm/sections.h>
+
+#include "mm.h"
+
+#ifndef CONFIG_CPU_V7M
+
+#define PRSEL __ACCESS_CP15(c6, 0, c2, 1)
+#define PRBAR __ACCESS_CP15(c6, 0, c3, 0)
+#define PRLAR __ACCESS_CP15(c6, 0, c3, 1)
+
+static inline u32 prlar_read(void)
+{
+ return read_sysreg(PRLAR);
+}
+
+static inline u32 prbar_read(void)
+{
+ return read_sysreg(PRBAR);
+}
+
+static inline void prsel_write(u32 v)
+{
+ write_sysreg(v, PRSEL);
+}
+
+static inline void prbar_write(u32 v)
+{
+ write_sysreg(v, PRBAR);
+}
+
+static inline void prlar_write(u32 v)
+{
+ write_sysreg(v, PRLAR);
+}
+#else
+
+static inline u32 prlar_read(void)
+{
+ return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RLAR);
+}
+
+static inline u32 prbar_read(void)
+{
+ return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RBAR);
+}
+
+static inline void prsel_write(u32 v)
+{
+ writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RNR);
+}
+
+static inline void prbar_write(u32 v)
+{
+ writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RBAR);
+}
+
+static inline void prlar_write(u32 v)
+{
+ writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RLAR);
+}
+
+#endif
+
+static struct range __initdata io[MPU_MAX_REGIONS];
+static struct range __initdata mem[MPU_MAX_REGIONS];
+
+static unsigned int __initdata mpu_max_regions;
+
+static __init bool is_region_reserved(int number)
+{
+ switch (number) {
+ case PMSAv8_XIP_REGION:
+ case PMSAv8_KERNEL_REGION:
+ return true;
+ default:
+ return false;
+ }
+}
+
+void __init pmsav8_adjust_lowmem_bounds(void)
+{
+ phys_addr_t mem_end;
+ struct memblock_region *reg;
+ bool first = true;
+
+ for_each_memblock(memory, reg) {
+ if (first) {
+ phys_addr_t phys_offset = PHYS_OFFSET;
+
+ /*
+ * Initially only use memory continuous from
+ * PHYS_OFFSET */
+ if (reg->base != phys_offset)
+ panic("First memory bank must be contiguous from PHYS_OFFSET");
+ mem_end = reg->base + reg->size;
+ first = false;
+ } else {
+ /*
+ * memblock auto merges contiguous blocks, remove
+ * all blocks afterwards in one go (we can't remove
+ * blocks separately while iterating)
+ */
+ pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
+ &mem_end, ®->base);
+ memblock_remove(reg->base, 0 - reg->base);
+ break;
+ }
+ }
+}
+
+static int __init __mpu_max_regions(void)
+{
+ static int max_regions;
+ u32 mpuir;
+
+ if (max_regions)
+ return max_regions;
+
+ mpuir = read_cpuid_mputype();
+
+ max_regions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION;
+
+ return max_regions;
+}
+
+static int __init __pmsav8_setup_region(unsigned int number, u32 bar, u32 lar)
+{
+ if (number > mpu_max_regions
+ || number >= MPU_MAX_REGIONS)
+ return -ENOENT;
+
+ dsb();
+ prsel_write(number);
+ isb();
+ prbar_write(bar);
+ prlar_write(lar);
+
+ mpu_rgn_info.rgns[number].prbar = bar;
+ mpu_rgn_info.rgns[number].prlar = lar;
+
+ mpu_rgn_info.used++;
+
+ return 0;
+}
+
+static int __init pmsav8_setup_ram(unsigned int number, phys_addr_t start,phys_addr_t end)
+{
+ u32 bar, lar;
+
+ if (is_region_reserved(number))
+ return -EINVAL;
+
+ bar = start;
+ lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);;
+
+ bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED;
+ lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
+
+ return __pmsav8_setup_region(number, bar, lar);
+}
+
+static int __init pmsav8_setup_io(unsigned int number, phys_addr_t start,phys_addr_t end)
+{
+ u32 bar, lar;
+
+ if (is_region_reserved(number))
+ return -EINVAL;
+
+ bar = start;
+ lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);;
+
+ bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN;
+ lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN;
+
+ return __pmsav8_setup_region(number, bar, lar);
+}
+
+static int __init pmsav8_setup_reserved(unsigned int number, phys_addr_t start,phys_addr_t end)
+{
+ u32 bar, lar;
+
+ if (!is_region_reserved(number))
+ return -EINVAL;
+
+ bar = start;
+ lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
+
+ bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED;
+ lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
+
+ prsel_write(number);
+ isb();
+
+ if (prbar_read() != bar || prlar_read() != lar)
+ return -EINVAL;
+
+ /* Reserved region was set up early, we just need a record for secondaries */
+ mpu_rgn_info.rgns[number].prbar = bar;
+ mpu_rgn_info.rgns[number].prlar = lar;
+
+ mpu_rgn_info.used++;
+
+ return 0;
+}
+
+#ifndef CONFIG_CPU_V7M
+static int __init pmsav8_setup_vector(unsigned int number, phys_addr_t start,phys_addr_t end)
+{
+ u32 bar, lar;
+
+ if (number == PMSAv8_KERNEL_REGION)
+ return -EINVAL;
+
+ bar = start;
+ lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);
+
+ bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED;
+ lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN;
+
+ return __pmsav8_setup_region(number, bar, lar);
+}
+#endif
+
+void __init pmsav8_setup(void)
+{
+ int i, err = 0;
+ int region = PMSAv8_KERNEL_REGION;
+
+ /* How many regions are supported ? */
+ mpu_max_regions = __mpu_max_regions();
+
+ /* RAM: single chunk of memory */
+ add_range(mem, ARRAY_SIZE(mem), 0, memblock.memory.regions[0].base,
+ memblock.memory.regions[0].base + memblock.memory.regions[0].size);
+
+ /* IO: cover full 4G range */
+ add_range(io, ARRAY_SIZE(io), 0, 0, 0xffffffff);
+
+ /* RAM and IO: exclude kernel */
+ subtract_range(mem, ARRAY_SIZE(mem), __pa(KERNEL_START), __pa(KERNEL_END));
+ subtract_range(io, ARRAY_SIZE(io), __pa(KERNEL_START), __pa(KERNEL_END));
+
+#ifdef CONFIG_XIP_KERNEL
+ /* RAM and IO: exclude xip */
+ subtract_range(mem, ARRAY_SIZE(mem), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
+ subtract_range(io, ARRAY_SIZE(io), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
+#endif
+
+#ifndef CONFIG_CPU_V7M
+ /* RAM and IO: exclude vectors */
+ subtract_range(mem, ARRAY_SIZE(mem), vectors_base, vectors_base + 2 * PAGE_SIZE);
+ subtract_range(io, ARRAY_SIZE(io), vectors_base, vectors_base + 2 * PAGE_SIZE);
+#endif
+ /* IO: exclude RAM */
+ for (i = 0; i < ARRAY_SIZE(mem); i++)
+ subtract_range(io, ARRAY_SIZE(io), mem[i].start, mem[i].end);
+
+ /* Now program MPU */
+
+#ifdef CONFIG_XIP_KERNEL
+ /* ROM */
+ err |= pmsav8_setup_reserved(PMSAv8_XIP_REGION, CONFIG_XIP_PHYS_ADDR, __pa(_exiprom));
+#endif
+ /* Kernel */
+ err |= pmsav8_setup_reserved(region++, __pa(KERNEL_START), __pa(KERNEL_END));
+
+
+ /* IO */
+ for (i = 0; i < ARRAY_SIZE(io); i++) {
+ if (!io[i].end)
+ continue;
+
+ err |= pmsav8_setup_io(region++, io[i].start, io[i].end);
+ }
+
+ /* RAM */
+ for (i = 0; i < ARRAY_SIZE(mem); i++) {
+ if (!mem[i].end)
+ continue;
+
+ err |= pmsav8_setup_ram(region++, mem[i].start, mem[i].end);
+ }
+
+ /* Vectors */
+#ifndef CONFIG_CPU_V7M
+ err |= pmsav8_setup_vector(region++, vectors_base, vectors_base + 2 * PAGE_SIZE);
+#endif
+ if (err)
+ pr_warn("MPU region initialization failure! %d", err);
+ else
+ pr_info("Using ARM PMSAv8 Compliant MPU. Used %d of %d regions\n",
+ mpu_rgn_info.used, mpu_max_regions);
+}
--
2.0.0
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