[PATCH 01/02] ARM: shmobile: Introduce per-CPU SMP boot / sleep code
From: horms@verge.net.au (Simon Horman)
Date: 2013-08-05 08:34:52
Also in:
linux-sh
On Thu, Aug 01, 2013 at 03:38:18AM +0900, Magnus Damm wrote:
From: Magnus Damm <redacted> Add per-CPU SMP boot / sleep code that can be used by all SoCs included in mach-shmobile. The boot code reads out the per-CPU MPIDR id value and matches it with the value stored for any CPU number, and if there is a match and the boot function is set as well then the boot function will be executed. The sleep code simply uses WFI and then jumps back to the boot code to see if anyone has asked to wake up that CPU, if not it will sleep again. Signed-off-by: Magnus Damm <redacted>
Hi Magnus, I have queued this up for v3.12 in the smp branch with the following whitespace changes:
quoted hunk ↗ jump to hunk
--- arch/arm/mach-shmobile/headsmp.S | 50 ++++++++++++++++++++++++++ arch/arm/mach-shmobile/include/mach/common.h | 4 ++ arch/arm/mach-shmobile/platsmp.c | 18 +++++++++ 3 files changed, 72 insertions(+)--- 0001/arch/arm/mach-shmobile/headsmp.S +++ work/arch/arm/mach-shmobile/headsmp.S 2013-07-31 12:23:20.000000000 +0900@@ -40,3 +40,53 @@ shmobile_boot_fn: .globl shmobile_boot_arg shmobile_boot_arg: 2: .space 4 + +/* + * Per-CPU SMP boot function/argument selection code based on MPIDR + */ + +ENTRY(shmobile_smp_boot) + @ r0 = MPIDR_HWID_BITMASK + mrc p15, 0, r1, c0, c0, 5 @ r1 = MPIDR + and r0, r1, r0 @ r0 = cpu_logical_map() value + mov r1, #0 @ r1 = CPU index + adr r5, 1f @ array of per-cpu mpidr values + adr r6, 2f @ array of per-cpu functions + adr r7, 3f @ array of per-cpu arguments +
Removed trailing whitespace from line above.
+shmobile_smp_boot_find_mpidr: + ldr r8, [r5, r1, lsl #2] + cmp r8, r0 + bne shmobile_smp_boot_next + + ldr r9, [r6, r1, lsl #2] + cmp r9, #0 + bne shmobile_smp_boot_found +
Removed trailing whitespace from line above.
+shmobile_smp_boot_next: + add r1, r1, #1 + cmp r1, #CONFIG_NR_CPUS + blo shmobile_smp_boot_find_mpidr + + b shmobile_smp_sleep +
Removed trailing whitespace from line above.
+shmobile_smp_boot_found: + ldr r0, [r7, r1, lsl #2] + mov pc, r9 +ENDPROC(shmobile_smp_boot) + +ENTRY(shmobile_smp_sleep) + wfi + b shmobile_smp_boot +ENDPROC(shmobile_smp_sleep) + + .globl shmobile_smp_mpidr +shmobile_smp_mpidr: +1: .space CONFIG_NR_CPUS * 4 + .globl shmobile_smp_fn +shmobile_smp_fn: +2: .space CONFIG_NR_CPUS * 4 + .globl shmobile_smp_arg +shmobile_smp_arg: +3: .space CONFIG_NR_CPUS * 4 +
Remove trailing blank line from line above.
quoted hunk ↗ jump to hunk
--- 0006/arch/arm/mach-shmobile/include/mach/common.h +++ work/arch/arm/mach-shmobile/include/mach/common.h 2013-07-31 12:18:01.000000000 +0900@@ -10,6 +10,10 @@ extern void shmobile_setup_console(void) extern void shmobile_boot_vector(void); extern unsigned long shmobile_boot_fn; extern unsigned long shmobile_boot_arg; +extern void shmobile_smp_boot(void); +extern void shmobile_smp_sleep(void); +extern void shmobile_smp_hook(unsigned int cpu, unsigned long fn, + unsigned long arg); extern void shmobile_boot_scu(void); extern void shmobile_smp_scu_prepare_cpus(unsigned int max_cpus); extern int shmobile_smp_scu_boot_secondary(unsigned int cpu, --- 0001/arch/arm/mach-shmobile/platsmp.c +++ work/arch/arm/mach-shmobile/platsmp.c 2013-07-31 12:18:01.000000000 +0900@@ -12,6 +12,9 @@ */ #include <linux/init.h> #include <linux/smp.h> +#include <asm/cacheflush.h> +#include <asm/smp_plat.h> +#include <mach/common.h> void __init shmobile_smp_init_cpus(unsigned int ncores) {@@ -26,3 +29,18 @@ void __init shmobile_smp_init_cpus(unsig for (i = 0; i < ncores; i++) set_cpu_possible(i, true); } + +extern unsigned long shmobile_smp_fn[]; +extern unsigned long shmobile_smp_arg[]; +extern unsigned long shmobile_smp_mpidr[]; + +void shmobile_smp_hook(unsigned int cpu, unsigned long fn, unsigned long arg) +{ + shmobile_smp_fn[cpu] = 0; + flush_cache_all(); + + shmobile_smp_mpidr[cpu] = cpu_logical_map(cpu); + shmobile_smp_fn[cpu] = fn; + shmobile_smp_arg[cpu] = arg; + flush_cache_all(); +}