ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type
When hotplug CPU is enabled, we need to keep the list of supported CPUs,
their setup functions, and __lookup_processor_type in place so that we
can find and initialize secondary CPUs. Move these into the __CPUINIT
section.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S
index b9505aa..6ad24d2 100644
--- a/arch/arm/kernel/head-common.S
+++ b/arch/arm/kernel/head-common.S
@@ -145,45 +145,14 @@
/*
- * Read processor ID register (CP#15, CR0), and look up in the linker-built
- * supported processor list. Note that we can't use the absolute addresses
- * for the __proc_info lists since we aren't running with the MMU on
- * (and therefore, we are not in the correct address space). We have to
- * calculate the offset.
- *
- * r9 = cpuid
- * Returns:
- * r3, r4, r6 corrupted
- * r5 = proc_info pointer in physical address space
- * r9 = cpuid (preserved)
- */
-__lookup_processor_type:
- adr r3, 3f
- ldmia r3, {r5 - r7}
- add r3, r3, #8
- sub r3, r3, r7 @ get offset between virt&phys
- add r5, r5, r3 @ convert virt addresses to
- add r6, r6, r3 @ physical address space
-1: ldmia r5, {r3, r4} @ value, mask
- and r4, r4, r9 @ mask wanted bits
- teq r3, r4
- beq 2f
- add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list)
- cmp r5, r6
- blo 1b
- mov r5, #0 @ unknown processor
-2: mov pc, lr
-ENDPROC(__lookup_processor_type)
-
-/*
- * This provides a C-API version of the above function.
+ * This provides a C-API version of __lookup_processor_type
*/
ENTRY(lookup_processor_type)
- stmfd sp!, {r4 - r7, r9, lr}
+ stmfd sp!, {r4 - r6, r9, lr}
mov r9, r0
bl __lookup_processor_type
mov r0, r5
- ldmfd sp!, {r4 - r7, r9, pc}
+ ldmfd sp!, {r4 - r6, r9, pc}
ENDPROC(lookup_processor_type)
/*
@@ -191,8 +160,6 @@
* more information about the __proc_info and __arch_info structures.
*/
.align 2
-3: .long __proc_info_begin
- .long __proc_info_end
4: .long .
.long __arch_info_begin
.long __arch_info_end
@@ -265,3 +232,45 @@
1: mov r2, #0
mov pc, lr
ENDPROC(__vet_atags)
+
+/*
+ * Read processor ID register (CP#15, CR0), and look up in the linker-built
+ * supported processor list. Note that we can't use the absolute addresses
+ * for the __proc_info lists since we aren't running with the MMU on
+ * (and therefore, we are not in the correct address space). We have to
+ * calculate the offset.
+ *
+ * r9 = cpuid
+ * Returns:
+ * r3, r4, r6 corrupted
+ * r5 = proc_info pointer in physical address space
+ * r9 = cpuid (preserved)
+ */
+ __CPUINIT
+__lookup_processor_type:
+ adr r3, __lookup_processor_type_data
+ ldmia r3, {r4 - r6}
+ sub r3, r3, r4 @ get offset between virt&phys
+ add r5, r5, r3 @ convert virt addresses to
+ add r6, r6, r3 @ physical address space
+1: ldmia r5, {r3, r4} @ value, mask
+ and r4, r4, r9 @ mask wanted bits
+ teq r3, r4
+ beq 2f
+ add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list)
+ cmp r5, r6
+ blo 1b
+ mov r5, #0 @ unknown processor
+2: mov pc, lr
+ENDPROC(__lookup_processor_type)
+
+/*
+ * Look in <asm/procinfo.h> for information about the __proc_info structure.
+ */
+ .align 2
+ .type __lookup_processor_type_data, %object
+__lookup_processor_type_data:
+ .long .
+ .long __proc_info_begin
+ .long __proc_info_end
+ .size __lookup_processor_type_data, . - __lookup_processor_type_data
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index b16c079..1630524 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -8,6 +8,19 @@
#include <asm/memory.h>
#include <asm/page.h>
+#define PROC_INFO \
+ VMLINUX_SYMBOL(__proc_info_begin) = .; \
+ *(.proc.info.init) \
+ VMLINUX_SYMBOL(__proc_info_end) = .;
+
+#ifdef CONFIG_HOTPLUG_CPU
+#define ARM_CPU_DISCARD(x)
+#define ARM_CPU_KEEP(x) x
+#else
+#define ARM_CPU_DISCARD(x) x
+#define ARM_CPU_KEEP(x)
+#endif
+
OUTPUT_ARCH(arm)
ENTRY(stext)
@@ -31,9 +44,7 @@
HEAD_TEXT
INIT_TEXT
_einittext = .;
- __proc_info_begin = .;
- *(.proc.info.init)
- __proc_info_end = .;
+ ARM_CPU_DISCARD(PROC_INFO)
__arch_info_begin = .;
*(.arch.info.init)
__arch_info_end = .;
@@ -68,10 +79,8 @@
/DISCARD/ : {
*(.ARM.exidx.exit.text)
*(.ARM.extab.exit.text)
-#ifndef CONFIG_HOTPLUG_CPU
- *(.ARM.exidx.cpuexit.text)
- *(.ARM.extab.cpuexit.text)
-#endif
+ ARM_CPU_DISCARD(*(.ARM.exidx.cpuexit.text))
+ ARM_CPU_DISCARD(*(.ARM.extab.cpuexit.text))
#ifndef CONFIG_HOTPLUG
*(.ARM.exidx.devexit.text)
*(.ARM.extab.devexit.text)
@@ -100,6 +109,7 @@
*(.glue_7)
*(.glue_7t)
*(.got) /* Global offset table */
+ ARM_CPU_KEEP(PROC_INFO)
}
RO_DATA(PAGE_SIZE)