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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-29 15:06:00 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-29 15:06:00 -0700
commitdd96a8e056e7b3e480197ff2cdf106b46455d779 (patch)
tree7958f4d6fb3714f585e13e2e9ecb3dfa6d8a8223 /arch
parenta879cbbb34cbecfa9707fbb6e5a00c503ac1ecb9 (diff)
parent53e173f62c318e65e6ae13524b04c5cf38c1bc3c (diff)
Merge of master.kernel.org:/home/rmk/linux-2.6-rmk.git
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/configs/ixdp2800_defconfig2
-rw-r--r--arch/arm/kernel/entry-armv.S213
-rw-r--r--arch/arm/kernel/traps.c58
-rw-r--r--arch/arm/mach-ixp2000/ixdp2800.c147
-rw-r--r--arch/arm/mach-ixp2000/pci.c8
-rw-r--r--arch/arm/mm/Kconfig14
-rw-r--r--arch/arm/mm/abort-ev6.S16
-rw-r--r--arch/arm/mm/mm-armv.c5
8 files changed, 434 insertions, 29 deletions
diff --git a/arch/arm/configs/ixdp2800_defconfig b/arch/arm/configs/ixdp2800_defconfig
index d36f9919296..7be3521f91f 100644
--- a/arch/arm/configs/ixdp2800_defconfig
+++ b/arch/arm/configs/ixdp2800_defconfig
@@ -133,7 +133,7 @@ CONFIG_ALIGNMENT_TRAP=y
#
CONFIG_ZBOOT_ROM_TEXT=0x0
CONFIG_ZBOOT_ROM_BSS=0x0
-CONFIG_CMDLINE="console=ttyS0,9600 root=/dev/nfs ip=bootp mem=64M@0x0 pci=firmware"
+CONFIG_CMDLINE="console=ttyS0,9600 root=/dev/nfs ip=bootp mem=64M@0x0"
# CONFIG_XIP_KERNEL is not set
#
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 2a5c3fe09a9..080df907f24 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -269,6 +269,12 @@ __pabt_svc:
add r5, sp, #S_PC
ldmia r7, {r2 - r4} @ Get USR pc, cpsr
+#if __LINUX_ARM_ARCH__ < 6
+ @ make sure our user space atomic helper is aborted
+ cmp r2, #VIRT_OFFSET
+ bichs r3, r3, #PSR_Z_BIT
+#endif
+
@
@ We are now ready to fill in the remaining blanks on the stack:
@
@@ -499,8 +505,12 @@ ENTRY(__switch_to)
mra r4, r5, acc0
stmia ip, {r4, r5}
#endif
+#ifdef CONFIG_HAS_TLS_REG
+ mcr p15, 0, r3, c13, c0, 3 @ set TLS register
+#else
mov r4, #0xffff0fff
- str r3, [r4, #-3] @ Set TLS ptr
+ str r3, [r4, #-15] @ TLS val at 0xffff0ff0
+#endif
mcr p15, 0, r6, c3, c0, 0 @ Set domain register
#ifdef CONFIG_VFP
@ Always disable VFP so we can lazily save/restore the old
@@ -519,6 +529,207 @@ ENTRY(__switch_to)
ldmib r2, {r4 - sl, fp, sp, pc} @ Load all regs saved previously
__INIT
+
+/*
+ * User helpers.
+ *
+ * These are segment of kernel provided user code reachable from user space
+ * at a fixed address in kernel memory. This is used to provide user space
+ * with some operations which require kernel help because of unimplemented
+ * native feature and/or instructions in many ARM CPUs. The idea is for
+ * this code to be executed directly in user mode for best efficiency but
+ * which is too intimate with the kernel counter part to be left to user
+ * libraries. In fact this code might even differ from one CPU to another
+ * depending on the available instruction set and restrictions like on
+ * SMP systems. In other words, the kernel reserves the right to change
+ * this code as needed without warning. Only the entry points and their
+ * results are guaranteed to be stable.
+ *
+ * Each segment is 32-byte aligned and will be moved to the top of the high
+ * vector page. New segments (if ever needed) must be added in front of
+ * existing ones. This mechanism should be used only for things that are
+ * really small and justified, and not be abused freely.
+ *
+ * User space is expected to implement those things inline when optimizing
+ * for a processor that has the necessary native support, but only if such
+ * resulting binaries are already to be incompatible with earlier ARM
+ * processors due to the use of unsupported instructions other than what
+ * is provided here. In other words don't make binaries unable to run on
+ * earlier processors just for the sake of not using these kernel helpers
+ * if your compiled code is not going to use the new instructions for other
+ * purpose.
+ */
+
+ .align 5
+ .globl __kuser_helper_start
+__kuser_helper_start:
+
+/*
+ * Reference prototype:
+ *
+ * int __kernel_cmpxchg(int oldval, int newval, int *ptr)
+ *
+ * Input:
+ *
+ * r0 = oldval
+ * r1 = newval
+ * r2 = ptr
+ * lr = return address
+ *
+ * Output:
+ *
+ * r0 = returned value (zero or non-zero)
+ * C flag = set if r0 == 0, clear if r0 != 0
+ *
+ * Clobbered:
+ *
+ * r3, ip, flags
+ *
+ * Definition and user space usage example:
+ *
+ * typedef int (__kernel_cmpxchg_t)(int oldval, int newval, int *ptr);
+ * #define __kernel_cmpxchg (*(__kernel_cmpxchg_t *)0xffff0fc0)
+ *
+ * Atomically store newval in *ptr if *ptr is equal to oldval for user space.
+ * Return zero if *ptr was changed or non-zero if no exchange happened.
+ * The C flag is also set if *ptr was changed to allow for assembly
+ * optimization in the calling code.
+ *
+ * For example, a user space atomic_add implementation could look like this:
+ *
+ * #define atomic_add(ptr, val) \
+ * ({ register unsigned int *__ptr asm("r2") = (ptr); \
+ * register unsigned int __result asm("r1"); \
+ * asm volatile ( \
+ * "1: @ atomic_add\n\t" \
+ * "ldr r0, [r2]\n\t" \
+ * "mov r3, #0xffff0fff\n\t" \
+ * "add lr, pc, #4\n\t" \
+ * "add r1, r0, %2\n\t" \
+ * "add pc, r3, #(0xffff0fc0 - 0xffff0fff)\n\t" \
+ * "bcc 1b" \
+ * : "=&r" (__result) \
+ * : "r" (__ptr), "rIL" (val) \
+ * : "r0","r3","ip","lr","cc","memory" ); \
+ * __result; })
+ */
+
+__kuser_cmpxchg: @ 0xffff0fc0
+
+#if __LINUX_ARM_ARCH__ < 6
+
+#ifdef CONFIG_SMP /* sanity check */
+#error "CONFIG_SMP on a machine supporting pre-ARMv6 processors?"
+#endif
+
+ /*
+ * Theory of operation:
+ *
+ * We set the Z flag before loading oldval. If ever an exception
+ * occurs we can not be sure the loaded value will still be the same
+ * when the exception returns, therefore the user exception handler
+ * will clear the Z flag whenever the interrupted user code was
+ * actually from the kernel address space (see the usr_entry macro).
+ *
+ * The post-increment on the str is used to prevent a race with an
+ * exception happening just after the str instruction which would
+ * clear the Z flag although the exchange was done.
+ */
+ teq ip, ip @ set Z flag
+ ldr ip, [r2] @ load current val
+ add r3, r2, #1 @ prepare store ptr
+ teqeq ip, r0 @ compare with oldval if still allowed
+ streq r1, [r3, #-1]! @ store newval if still allowed
+ subs r0, r2, r3 @ if r2 == r3 the str occured
+ mov pc, lr
+
+#else
+
+ ldrex r3, [r2]
+ subs r3, r3, r0
+ strexeq r3, r1, [r2]
+ rsbs r0, r3, #0
+ mov pc, lr
+
+#endif
+
+ .align 5
+
+/*
+ * Reference prototype:
+ *
+ * int __kernel_get_tls(void)
+ *
+ * Input:
+ *
+ * lr = return address
+ *
+ * Output:
+ *
+ * r0 = TLS value
+ *
+ * Clobbered:
+ *
+ * the Z flag might be lost
+ *
+ * Definition and user space usage example:
+ *
+ * typedef int (__kernel_get_tls_t)(void);
+ * #define __kernel_get_tls (*(__kernel_get_tls_t *)0xffff0fe0)
+ *
+ * Get the TLS value as previously set via the __ARM_NR_set_tls syscall.
+ *
+ * This could be used as follows:
+ *
+ * #define __kernel_get_tls() \
+ * ({ register unsigned int __val asm("r0"); \
+ * asm( "mov r0, #0xffff0fff; mov lr, pc; sub pc, r0, #31" \
+ * : "=r" (__val) : : "lr","cc" ); \
+ * __val; })
+ */
+
+__kuser_get_tls: @ 0xffff0fe0
+
+#ifndef CONFIG_HAS_TLS_REG
+
+#ifdef CONFIG_SMP /* sanity check */
+#error "CONFIG_SMP without CONFIG_HAS_TLS_REG is wrong"
+#endif
+
+ ldr r0, [pc, #(16 - 8)] @ TLS stored at 0xffff0ff0
+ mov pc, lr
+
+#else
+
+ mrc p15, 0, r0, c13, c0, 3 @ read TLS register
+ mov pc, lr
+
+#endif
+
+ .rep 5
+ .word 0 @ pad up to __kuser_helper_version
+ .endr
+
+/*
+ * Reference declaration:
+ *
+ * extern unsigned int __kernel_helper_version;
+ *
+ * Definition and user space usage example:
+ *
+ * #define __kernel_helper_version (*(unsigned int *)0xffff0ffc)
+ *
+ * User space may read this to determine the curent number of helpers
+ * available.
+ */
+
+__kuser_helper_version: @ 0xffff0ffc
+ .word ((__kuser_helper_end - __kuser_helper_start) >> 5)
+
+ .globl __kuser_helper_end
+__kuser_helper_end:
+
+
/*
* Vector stubs.
*
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 0078aeb8573..3a001fe5540 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -450,13 +450,17 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs)
case NR(set_tls):
thread->tp_value = regs->ARM_r0;
+#ifdef CONFIG_HAS_TLS_REG
+ asm ("mcr p15, 0, %0, c13, c0, 3" : : "r" (regs->ARM_r0) );
+#else
/*
- * Our user accessible TLS ptr is located at 0xffff0ffc.
- * On SMP read access to this address must raise a fault
- * and be emulated from the data abort handler.
- * m
+ * User space must never try to access this directly.
+ * Expect your app to break eventually if you do so.
+ * The user helper at 0xffff0fe0 must be used instead.
+ * (see entry-armv.S for details)
*/
- *((unsigned long *)0xffff0ffc) = thread->tp_value;
+ *((unsigned int *)0xffff0ff0) = regs->ARM_r0;
+#endif
return 0;
default:
@@ -493,6 +497,41 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs)
return 0;
}
+#if defined(CONFIG_CPU_32v6) && !defined(CONFIG_HAS_TLS_REG)
+
+/*
+ * We might be running on an ARMv6+ processor which should have the TLS
+ * register, but for some reason we can't use it and have to emulate it.
+ */
+
+static int get_tp_trap(struct pt_regs *regs, unsigned int instr)
+{
+ int reg = (instr >> 12) & 15;
+ if (reg == 15)
+ return 1;
+ regs->uregs[reg] = current_thread_info()->tp_value;
+ regs->ARM_pc += 4;
+ return 0;
+}
+
+static struct undef_hook arm_mrc_hook = {
+ .instr_mask = 0x0fff0fff,
+ .instr_val = 0x0e1d0f70,
+ .cpsr_mask = PSR_T_BIT,
+ .cpsr_val = 0,
+ .fn = get_tp_trap,
+};
+
+static int __init arm_mrc_hook_init(void)
+{
+ register_undef_hook(&arm_mrc_hook);
+ return 0;
+}
+
+late_initcall(arm_mrc_hook_init);
+
+#endif
+
void __bad_xchg(volatile void *ptr, int size)
{
printk("xchg: bad data size: pc 0x%p, ptr 0x%p, size %d\n",
@@ -580,14 +619,17 @@ void __init trap_init(void)
{
extern char __stubs_start[], __stubs_end[];
extern char __vectors_start[], __vectors_end[];
+ extern char __kuser_helper_start[], __kuser_helper_end[];
+ int kuser_sz = __kuser_helper_end - __kuser_helper_start;
/*
- * Copy the vectors and stubs (in entry-armv.S) into the
- * vector page, mapped at 0xffff0000, and ensure these are
- * visible to the instruction stream.
+ * Copy the vectors, stubs and kuser helpers (in entry-armv.S)
+ * into the vector page, mapped at 0xffff0000, and ensure these
+ * are visible to the instruction stream.
*/
memcpy((void *)0xffff0000, __vectors_start, __vectors_end - __vectors_start);
memcpy((void *)0xffff0200, __stubs_start, __stubs_end - __stubs_start);
+ memcpy((void *)0xffff1000 - kuser_sz, __kuser_helper_start, kuser_sz);
flush_icache_range(0xffff0000, 0xffff0000 + PAGE_SIZE);
modify_domain(DOMAIN_USER, DOMAIN_CLIENT);
}
diff --git a/arch/arm/mach-ixp2000/ixdp2800.c b/arch/arm/mach-ixp2000/ixdp2800.c
index c4683aaff84..aec13c7108a 100644
--- a/arch/arm/mach-ixp2000/ixdp2800.c
+++ b/arch/arm/mach-ixp2000/ixdp2800.c
@@ -65,19 +65,102 @@ static struct sys_timer ixdp2800_timer = {
/*************************************************************************
* IXDP2800 PCI
*************************************************************************/
+static void __init ixdp2800_slave_disable_pci_master(void)
+{
+ *IXP2000_PCI_CMDSTAT &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
+}
+
+static void __init ixdp2800_master_wait_for_slave(void)
+{
+ volatile u32 *addr;
+
+ printk(KERN_INFO "IXDP2800: waiting for slave NPU to configure "
+ "its BAR sizes\n");
+
+ addr = ixp2000_pci_config_addr(0, IXDP2X00_SLAVE_NPU_DEVFN,
+ PCI_BASE_ADDRESS_1);
+ do {
+ *addr = 0xffffffff;
+ cpu_relax();
+ } while (*addr != 0xfe000008);
+
+ addr = ixp2000_pci_config_addr(0, IXDP2X00_SLAVE_NPU_DEVFN,
+ PCI_BASE_ADDRESS_2);
+ do {
+ *addr = 0xffffffff;
+ cpu_relax();
+ } while (*addr != 0xc0000008);
+
+ /*
+ * Configure the slave's SDRAM BAR by hand.
+ */
+ *addr = 0x40000008;
+}
+
+static void __init ixdp2800_slave_wait_for_master_enable(void)
+{
+ printk(KERN_INFO "IXDP2800: waiting for master NPU to enable us\n");
+
+ while ((*IXP2000_PCI_CMDSTAT & PCI_COMMAND_MASTER) == 0)
+ cpu_relax();
+}
+
void __init ixdp2800_pci_preinit(void)
{
printk("ixdp2x00_pci_preinit called\n");
- *IXP2000_PCI_ADDR_EXT = 0x0000e000;
+ *IXP2000_PCI_ADDR_EXT = 0x0001e000;
+
+ if (!ixdp2x00_master_npu())
+ ixdp2800_slave_disable_pci_master();
- *IXP2000_PCI_DRAM_BASE_ADDR_MASK = (0x40000000 - 1) & ~0xfffff;
*IXP2000_PCI_SRAM_BASE_ADDR_MASK = (0x2000000 - 1) & ~0x3ffff;
+ *IXP2000_PCI_DRAM_BASE_ADDR_MASK = (0x40000000 - 1) & ~0xfffff;
ixp2000_pci_preinit();
+
+ if (ixdp2x00_master_npu()) {
+ /*
+ * Wait until the slave set its SRAM/SDRAM BAR sizes
+ * correctly before we proceed to scan and enumerate
+ * the bus.
+ */
+ ixdp2800_master_wait_for_slave();
+
+ /*
+ * We configure the SDRAM BARs by hand because they
+ * are 1G and fall outside of the regular allocated
+ * PCI address space.
+ */
+ *IXP2000_PCI_SDRAM_BAR = 0x00000008;
+ } else {
+ /*
+ * Wait for the master to complete scanning the bus
+ * and assigning resources before we proceed to scan
+ * the bus ourselves. Set pci=firmware to honor the
+ * master's resource assignment.
+ */
+ ixdp2800_slave_wait_for_master_enable();
+ pcibios_setup("firmware");
+ }
}
-int ixdp2800_pci_setup(int nr, struct pci_sys_data *sys)
+/*
+ * We assign the SDRAM BARs for the two IXP2800 CPUs by hand, outside
+ * of the regular PCI window, because there's only 512M of outbound PCI
+ * memory window on each IXP, while we need 1G for each of the BARs.
+ */
+static void __devinit ixp2800_pci_fixup(struct pci_dev *dev)
+{
+ if (machine_is_ixdp2800()) {
+ dev->resource[2].start = 0;
+ dev->resource[2].end = 0;
+ dev->resource[2].flags = 0;
+ }
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IXP2800, ixp2800_pci_fixup);
+
+static int __init ixdp2800_pci_setup(int nr, struct pci_sys_data *sys)
{
sys->mem_offset = 0x00000000;
@@ -129,22 +212,47 @@ static int __init ixdp2800_pci_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
} else return IRQ_IXP2000_PCIB; /* Slave NIC interrupt */
}
-static void ixdp2800_pci_postinit(void)
+static void __init ixdp2800_master_enable_slave(void)
{
- struct pci_dev *dev;
+ volatile u32 *addr;
- if (ixdp2x00_master_npu()) {
- dev = pci_find_slot(1, IXDP2800_SLAVE_ENET_DEVFN);
- pci_remove_bus_device(dev);
- } else {
- dev = pci_find_slot(1, IXDP2800_MASTER_ENET_DEVFN);
- pci_remove_bus_device(dev);
+ printk(KERN_INFO "IXDP2800: enabling slave NPU\n");
+
+ addr = (volatile u32 *)ixp2000_pci_config_addr(0,
+ IXDP2X00_SLAVE_NPU_DEVFN,
+ PCI_COMMAND);
+
+ *addr |= PCI_COMMAND_MASTER;
+}
+static void __init ixdp2800_master_wait_for_slave_bus_scan(void)
+{
+ volatile u32 *addr;
+
+ printk(KERN_INFO "IXDP2800: waiting for slave to finish bus scan\n");
+
+ addr = (volatile u32 *)ixp2000_pci_config_addr(0,
+ IXDP2X00_SLAVE_NPU_DEVFN,
+ PCI_COMMAND);
+ while ((*addr & PCI_COMMAND_MEMORY) == 0)
+ cpu_relax();
+}
+
+static void __init ixdp2800_slave_signal_bus_scan_completion(void)
+{
+ printk(KERN_INFO "IXDP2800: bus scan done, signaling master\n");
+ *IXP2000_PCI_CMDSTAT |= PCI_COMMAND_MEMORY;
+}
+
+static void __init ixdp2800_pci_postinit(void)
+{
+ if (!ixdp2x00_master_npu()) {
ixdp2x00_slave_pci_postinit();
+ ixdp2800_slave_signal_bus_scan_completion();
}
}
-struct hw_pci ixdp2800_pci __initdata = {
+struct __initdata hw_pci ixdp2800_pci __initdata = {
.nr_controllers = 1,
.setup = ixdp2800_pci_setup,
.preinit = ixdp2800_pci_preinit,
@@ -155,8 +263,21 @@ struct hw_pci ixdp2800_pci __initdata = {
int __init ixdp2800_pci_init(void)
{
- if (machine_is_ixdp2800())
+ if (machine_is_ixdp2800()) {
+ struct pci_dev *dev;
+
pci_common_init(&ixdp2800_pci);
+ if (ixdp2x00_master_npu()) {
+ dev = pci_find_slot(1, IXDP2800_SLAVE_ENET_DEVFN);
+ pci_remove_bus_device(dev);
+
+ ixdp2800_master_enable_slave();
+ ixdp2800_master_wait_for_slave_bus_scan();
+ } else {
+ dev = pci_find_slot(1, IXDP2800_MASTER_ENET_DEVFN);
+ pci_remove_bus_device(dev);
+ }
+ }
return 0;
}
diff --git a/arch/arm/mach-ixp2000/pci.c b/arch/arm/mach-ixp2000/pci.c
index 831f8ffb6b6..5ff2f2718c5 100644
--- a/arch/arm/mach-ixp2000/pci.c
+++ b/arch/arm/mach-ixp2000/pci.c
@@ -37,7 +37,7 @@ static int pci_master_aborts = 0;
static int clear_master_aborts(void);
-static u32 *
+u32 *
ixp2000_pci_config_addr(unsigned int bus_nr, unsigned int devfn, int where)
{
u32 *paddress;
@@ -208,15 +208,15 @@ ixp2000_pci_preinit(void)
* use our own resource space.
*/
static struct resource ixp2000_pci_mem_space = {
- .start = 0x00000000,
+ .start = 0xe0000000,
.end = 0xffffffff,
.flags = IORESOURCE_MEM,
.name = "PCI Mem Space"
};
static struct resource ixp2000_pci_io_space = {
- .start = 0x00000000,
- .end = 0xffffffff,
+ .start = 0x00010000,
+ .end = 0x0001ffff,
.flags = IORESOURCE_IO,
.name = "PCI I/O Space"
};
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 5b670c9ac5e..007766a0644 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -409,3 +409,17 @@ config CPU_BPREDICT_DISABLE
depends on CPU_ARM1020
help
Say Y here to disable branch prediction. If unsure, say N.
+
+config HAS_TLS_REG
+ bool
+ depends on CPU_32v6 && !CPU_32v5 && !CPU_32v4 && !CPU_32v3
+ help
+ This selects support for the CP15 thread register.
+ It is defined to be available on ARMv6 or later. However
+ if the kernel is configured to support multiple CPUs including
+ a pre-ARMv6 processors, or if a given ARMv6 processor doesn't
+ implement the thread register for some reason, then access to
+ this register from user space must be trapped and emulated.
+ If user space is relying on the __kuser_get_tls code then
+ there should not be any impact.
+
diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S
index 38b2cbb89be..8f76f3df7b4 100644
--- a/arch/arm/mm/abort-ev6.S
+++ b/arch/arm/mm/abort-ev6.S
@@ -1,5 +1,6 @@
#include <linux/linkage.h>
#include <asm/assembler.h>
+#include "abort-macro.S"
/*
* Function: v6_early_abort
*
@@ -13,11 +14,26 @@
* : sp = pointer to registers
*
* Purpose : obtain information about current aborted instruction.
+ * Note: we read user space. This means we might cause a data
+ * abort here if the I-TLB and D-TLB aren't seeing the same
+ * picture. Unfortunately, this does happen. We live with it.
*/
.align 5
ENTRY(v6_early_abort)
mrc p15, 0, r1, c5, c0, 0 @ get FSR
mrc p15, 0, r0, c6, c0, 0 @ get FAR
+/*
+ * Faulty SWP instruction on 1136 doesn't set bit 11 in DFSR.
+ * The test below covers all the write situations, including Java bytecodes
+ */
+ bic r1, r1, #1 << 11 | 1 << 10 @ clear bits 11 and 10 of FSR
+ tst r3, #PSR_J_BIT @ Java?
+ movne pc, lr
+ do_thumb_abort
+ ldreq r3, [r2] @ read aborted ARM instruction
+ do_ldrd_abort
+ tst r3, #1 << 20 @ L = 0 -> write
+ orreq r1, r1, #1 << 11 @ yes.
mov pc, lr
diff --git a/arch/arm/mm/mm-armv.c b/arch/arm/mm/mm-armv.c
index f5a87db8b49..585dfb8e20b 100644
--- a/arch/arm/mm/mm-armv.c
+++ b/arch/arm/mm/mm-armv.c
@@ -411,9 +411,10 @@ static void __init build_mem_type_table(void)
mem_types[MT_MEMORY].prot_sect &= ~PMD_BIT4;
mem_types[MT_ROM].prot_sect &= ~PMD_BIT4;
/*
- * Mark cache clean areas read only from SVC mode
- * and no access from userspace.
+ * Mark cache clean areas and XIP ROM read only
+ * from SVC mode and no access from userspace.
*/
+ mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
}