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authorLinus Torvalds <torvalds@linux-foundation.org>2017-02-28 11:50:53 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-28 11:50:53 -0800
commitd4f4cf77b37eaea58ef863a4cbc95dad3880b524 (patch)
treec1d6c963d55e7f9afaa4fc9a5c6d1438a43bb94d /arch/arm/mm/nommu.c
parentMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (diff)
parentMerge branches 'fixes' and 'misc'; commit 'kuser^{/add CPU_THUMB_CAPABLE to indicate}' into for-linus (diff)
downloadlinux-dev-d4f4cf77b37eaea58ef863a4cbc95dad3880b524.tar.xz
linux-dev-d4f4cf77b37eaea58ef863a4cbc95dad3880b524.zip
Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King: - nommu updates from Afzal Mohammed cleaning up the vectors support - allow DMA memory "mapping" for nommu Benjamin Gaignard - fixing a correctness issue with R_ARM_PREL31 relocations in the module linker - add strlen() prototype for the decompressor - support for DEBUG_VIRTUAL from Florian Fainelli - adjusting memory bounds after memory reservations have been registered - unipher cache handling updates from Masahiro Yamada - initrd and Thumb Kconfig cleanups * 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (23 commits) ARM: mm: round the initrd reservation to page boundaries ARM: mm: clean up initrd initialisation ARM: mm: move initrd init code out of arm_memblock_init() ARM: 8655/1: improve NOMMU definition of pgprot_*() ARM: 8654/1: decompressor: add strlen prototype ARM: 8652/1: cache-uniphier: clean up active way setup code ARM: 8651/1: cache-uniphier: include <linux/errno.h> instead of <linux/types.h> ARM: 8650/1: module: handle negative R_ARM_PREL31 addends correctly ARM: 8649/2: nommu: remove Hivecs configuration is asm ARM: 8648/2: nommu: display vectors base ARM: 8647/2: nommu: dynamic exception base address setting ARM: 8646/1: mmu: decouple VECTORS_BASE from Kconfig ARM: 8644/1: Reduce "CPU: shutdown" message to debug level ARM: 8641/1: treewide: Replace uses of virt_to_phys with __pa_symbol ARM: 8640/1: Add support for CONFIG_DEBUG_VIRTUAL ARM: 8639/1: Define KERNEL_START and KERNEL_END ARM: 8638/1: mtd: lart: Rename partition defines to be prefixed with PART_ ARM: 8637/1: Adjust memory boundaries after reservations ARM: 8636/1: Cleanup sanity_check_meminfo ARM: add CPU_THUMB_CAPABLE to indicate possible Thumb support ...
Diffstat (limited to 'arch/arm/mm/nommu.c')
-rw-r--r--arch/arm/mm/nommu.c60
1 files changed, 54 insertions, 6 deletions
diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c
index 2740967727e2..3b5c7aaf9c76 100644
--- a/arch/arm/mm/nommu.c
+++ b/arch/arm/mm/nommu.c
@@ -11,6 +11,7 @@
#include <linux/kernel.h>
#include <asm/cacheflush.h>
+#include <asm/cp15.h>
#include <asm/sections.h>
#include <asm/page.h>
#include <asm/setup.h>
@@ -22,6 +23,8 @@
#include "mm.h"
+unsigned long vectors_base;
+
#ifdef CONFIG_ARM_MPU
struct mpu_rgn_info mpu_rgn_info;
@@ -85,7 +88,7 @@ static unsigned long irbar_read(void)
}
/* MPU initialisation functions */
-void __init sanity_check_meminfo_mpu(void)
+void __init adjust_lowmem_bounds_mpu(void)
{
phys_addr_t phys_offset = PHYS_OFFSET;
phys_addr_t aligned_region_size, specified_mem_size, rounded_mem_size;
@@ -274,19 +277,64 @@ void __init mpu_setup(void)
}
}
#else
-static void sanity_check_meminfo_mpu(void) {}
+static void adjust_lowmem_bounds_mpu(void) {}
static void __init mpu_setup(void) {}
#endif /* CONFIG_ARM_MPU */
+#ifdef CONFIG_CPU_CP15
+#ifdef CONFIG_CPU_HIGH_VECTOR
+static unsigned long __init setup_vectors_base(void)
+{
+ unsigned long reg = get_cr();
+
+ set_cr(reg | CR_V);
+ return 0xffff0000;
+}
+#else /* CONFIG_CPU_HIGH_VECTOR */
+/* Write exception base address to VBAR */
+static inline void set_vbar(unsigned long val)
+{
+ asm("mcr p15, 0, %0, c12, c0, 0" : : "r" (val) : "cc");
+}
+
+/*
+ * Security extensions, bits[7:4], permitted values,
+ * 0b0000 - not implemented, 0b0001/0b0010 - implemented
+ */
+static inline bool security_extensions_enabled(void)
+{
+ return !!cpuid_feature_extract(CPUID_EXT_PFR1, 4);
+}
+
+static unsigned long __init setup_vectors_base(void)
+{
+ unsigned long base = 0, reg = get_cr();
+
+ set_cr(reg & ~CR_V);
+ if (security_extensions_enabled()) {
+ if (IS_ENABLED(CONFIG_REMAP_VECTORS_TO_RAM))
+ base = CONFIG_DRAM_BASE;
+ set_vbar(base);
+ } else if (IS_ENABLED(CONFIG_REMAP_VECTORS_TO_RAM)) {
+ if (CONFIG_DRAM_BASE != 0)
+ pr_err("Security extensions not enabled, vectors cannot be remapped to RAM, vectors base will be 0x00000000\n");
+ }
+
+ return base;
+}
+#endif /* CONFIG_CPU_HIGH_VECTOR */
+#endif /* CONFIG_CPU_CP15 */
+
void __init arm_mm_memblock_reserve(void)
{
#ifndef CONFIG_CPU_V7M
+ vectors_base = IS_ENABLED(CONFIG_CPU_CP15) ? setup_vectors_base() : 0;
/*
* Register the exception vector page.
* some architectures which the DRAM is the exception vector to trap,
* alloc_page breaks with error, although it is not NULL, but "0."
*/
- memblock_reserve(CONFIG_VECTORS_BASE, 2 * PAGE_SIZE);
+ memblock_reserve(vectors_base, 2 * PAGE_SIZE);
#else /* ifndef CONFIG_CPU_V7M */
/*
* There is no dedicated vector page on V7-M. So nothing needs to be
@@ -295,10 +343,10 @@ void __init arm_mm_memblock_reserve(void)
#endif
}
-void __init sanity_check_meminfo(void)
+void __init adjust_lowmem_bounds(void)
{
phys_addr_t end;
- sanity_check_meminfo_mpu();
+ adjust_lowmem_bounds_mpu();
end = memblock_end_of_DRAM();
high_memory = __va(end - 1) + 1;
memblock_set_current_limit(end);
@@ -310,7 +358,7 @@ void __init sanity_check_meminfo(void)
*/
void __init paging_init(const struct machine_desc *mdesc)
{
- early_trap_init((void *)CONFIG_VECTORS_BASE);
+ early_trap_init((void *)vectors_base);
mpu_setup();
bootmem_init();
}