ARM: hotplug cpu: setup 1:1 map for entire kernel image for secondary CPUs
Make the entire kernel image available for secondary CPUs rather
than just the first MB of memory. This allows the startup code
to appear in the cpuinit sections.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 40dc74f..1407054 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -33,6 +33,7 @@
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/processor.h>
+#include <asm/sections.h>
#include <asm/tlbflush.h>
#include <asm/ptrace.h>
#include <asm/localtimer.h>
@@ -67,12 +68,47 @@
IPI_CPU_STOP,
};
+static inline void identity_mapping_add(pgd_t *pgd, unsigned long start,
+ unsigned long end)
+{
+ unsigned long addr, prot;
+ pmd_t *pmd;
+
+ prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
+ if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
+ prot |= PMD_BIT4;
+
+ for (addr = start & PGDIR_MASK; addr < end;) {
+ pmd = pmd_offset(pgd + pgd_index(addr), addr);
+ pmd[0] = __pmd(addr | prot);
+ addr += SECTION_SIZE;
+ pmd[1] = __pmd(addr | prot);
+ addr += SECTION_SIZE;
+ flush_pmd_entry(pmd);
+ outer_clean_range(__pa(pmd), __pa(pmd + 1));
+ }
+}
+
+static inline void identity_mapping_del(pgd_t *pgd, unsigned long start,
+ unsigned long end)
+{
+ unsigned long addr;
+ pmd_t *pmd;
+
+ for (addr = start & PGDIR_MASK; addr < end; addr += PGDIR_SIZE) {
+ pmd = pmd_offset(pgd + pgd_index(addr), addr);
+ pmd[0] = __pmd(0);
+ pmd[1] = __pmd(0);
+ clean_pmd_entry(pmd);
+ outer_clean_range(__pa(pmd), __pa(pmd + 1));
+ }
+}
+
int __cpuinit __cpu_up(unsigned int cpu)
{
struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu);
struct task_struct *idle = ci->idle;
pgd_t *pgd;
- pmd_t *pmd;
int ret;
/*
@@ -101,11 +137,16 @@
* a 1:1 mapping for the physical address of the kernel.
*/
pgd = pgd_alloc(&init_mm);
- pmd = pmd_offset(pgd + pgd_index(PHYS_OFFSET), PHYS_OFFSET);
- *pmd = __pmd((PHYS_OFFSET & PGDIR_MASK) |
- PMD_TYPE_SECT | PMD_SECT_AP_WRITE);
- flush_pmd_entry(pmd);
- outer_clean_range(__pa(pmd), __pa(pmd + 1));
+ if (!pgd)
+ return -ENOMEM;
+
+ if (PHYS_OFFSET != PAGE_OFFSET) {
+#ifndef CONFIG_HOTPLUG_CPU
+ identity_mapping_add(pgd, __pa(__init_begin), __pa(__init_end));
+#endif
+ identity_mapping_add(pgd, __pa(_stext), __pa(_etext));
+ identity_mapping_add(pgd, __pa(_sdata), __pa(_edata));
+ }
/*
* We need to tell the secondary core where to find
@@ -143,8 +184,14 @@
secondary_data.stack = NULL;
secondary_data.pgdir = 0;
- *pmd = __pmd(0);
- clean_pmd_entry(pmd);
+ if (PHYS_OFFSET != PAGE_OFFSET) {
+#ifndef CONFIG_HOTPLUG_CPU
+ identity_mapping_del(pgd, __pa(__init_begin), __pa(__init_end));
+#endif
+ identity_mapping_del(pgd, __pa(_stext), __pa(_etext));
+ identity_mapping_del(pgd, __pa(_sdata), __pa(_edata));
+ }
+
pgd_free(&init_mm, pgd);
if (ret) {