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authorLinus Torvalds <torvalds@linux-foundation.org>2014-08-05 10:05:29 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-08-05 10:05:29 -0700
commitc489d98c8c81a898cfed6bec193cca2006f956aa (patch)
tree4cc9b571c9bb2380e6b11828cc843f3ceeb5dcf4 /arch/arm/common/mcpm_entry.c
parentf67d251a87ccb288a3a164c5226c6ee9ce8ea53d (diff)
parentf15bdfe4fb264ac30d9c176f898cbd52cfd1ffa9 (diff)
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King: "Included in this update: - perf updates from Will Deacon: The main changes are callchain stability fixes from Jean Pihet and event mapping and PMU name rework from Mark Rutland The latter is preparatory work for enabling some code re-use with arm64 in the future. - updates for nommu from Uwe Kleine-König: Two different fixes for the same problem making some ARM nommu configurations not boot since 3.6-rc1. The problem is that user_addr_max returned the biggest available RAM address which makes some copy_from_user variants fail to read from XIP memory. - deprecate legacy OMAP DMA API, in preparation for it's removal. The popular drivers have been converted over, leaving a very small number of rarely used drivers, which hopefully can be converted during the next cycle with a bit more visibility (and hopefully people popping out of the woodwork to help test) - more tweaks for BE systems, particularly with the kernel image format. In connection with this, I've cleaned up the way we generate the linker script for the decompressor. - removal of hard-coded assumptions of the kernel stack size, making everywhere depend on the value of THREAD_SIZE_ORDER. - MCPM updates from Nicolas Pitre. - Make it easier for proper CPU part number checks (which should always include the vendor field). - Assembly code optimisation - use the "bx" instruction when returning from a function on ARMv6+ rather than "mov pc, reg". - Save the last kernel misaligned fault location and report it via the procfs alignment file. - Clean up the way we create the initial stack frame, which is a repeated pattern in several different locations. - Support for 8-byte get_user(), needed for some DRM implementations. - mcs locking from Will Deacon. - Save and restore a few more Cortex-A9 registers (for errata workarounds) - Fix various aspects of the SWP emulation, and the ELF hwcap for the SWP instruction. - Update LPAE logic for pte_write and pmd_write to make it more correct. - Support for Broadcom Brahma15 CPU cores. - ARM assembly crypto updates from Ard Biesheuvel" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (53 commits) ARM: add comments to the early page table remap code ARM: 8122/1: smp_scu: enable SCU standby support ARM: 8121/1: smp_scu: use macro for SCU enable bit ARM: 8120/1: crypto: sha512: add ARM NEON implementation ARM: 8119/1: crypto: sha1: add ARM NEON implementation ARM: 8118/1: crypto: sha1/make use of common SHA-1 structures ARM: 8113/1: remove remaining definitions of PLAT_PHYS_OFFSET from <mach/memory.h> ARM: 8111/1: Enable erratum 798181 for Broadcom Brahma-B15 ARM: 8110/1: do CPU-specific init for Broadcom Brahma15 cores ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear ARM: hwcap: disable HWCAP_SWP if the CPU advertises it has exclusives ARM: SWP emulation: only initialise on ARMv7 CPUs ARM: SWP emulation: always enable when SMP is enabled ARM: 8103/1: save/restore Cortex-A9 CP15 registers on suspend/resume ARM: 8098/1: mcs lock: implement wfe-based polling for MCS locking ARM: 8091/2: add get_user() support for 8 byte types ARM: 8097/1: unistd.h: relocate comments back to place ARM: 8096/1: Describe required sort order for textofs-y (TEXT_OFFSET) ARM: 8090/1: add revision info for PL310 errata 588369 and 727915 ...
Diffstat (limited to 'arch/arm/common/mcpm_entry.c')
-rw-r--r--arch/arm/common/mcpm_entry.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/arm/common/mcpm_entry.c b/arch/arm/common/mcpm_entry.c
index f91136ab447e..3c165fc2dce2 100644
--- a/arch/arm/common/mcpm_entry.c
+++ b/arch/arm/common/mcpm_entry.c
@@ -12,11 +12,13 @@
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/irqflags.h>
+#include <linux/cpu_pm.h>
#include <asm/mcpm.h>
#include <asm/cacheflush.h>
#include <asm/idmap.h>
#include <asm/cputype.h>
+#include <asm/suspend.h>
extern unsigned long mcpm_entry_vectors[MAX_NR_CLUSTERS][MAX_CPUS_PER_CLUSTER];
@@ -146,6 +148,56 @@ int mcpm_cpu_powered_up(void)
return 0;
}
+#ifdef CONFIG_ARM_CPU_SUSPEND
+
+static int __init nocache_trampoline(unsigned long _arg)
+{
+ void (*cache_disable)(void) = (void *)_arg;
+ unsigned int mpidr = read_cpuid_mpidr();
+ unsigned int cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ unsigned int cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+ phys_reset_t phys_reset;
+
+ mcpm_set_entry_vector(cpu, cluster, cpu_resume);
+ setup_mm_for_reboot();
+
+ __mcpm_cpu_going_down(cpu, cluster);
+ BUG_ON(!__mcpm_outbound_enter_critical(cpu, cluster));
+ cache_disable();
+ __mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
+ __mcpm_cpu_down(cpu, cluster);
+
+ phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
+ phys_reset(virt_to_phys(mcpm_entry_point));
+ BUG();
+}
+
+int __init mcpm_loopback(void (*cache_disable)(void))
+{
+ int ret;
+
+ /*
+ * We're going to soft-restart the current CPU through the
+ * low-level MCPM code by leveraging the suspend/resume
+ * infrastructure. Let's play it safe by using cpu_pm_enter()
+ * in case the CPU init code path resets the VFP or similar.
+ */
+ local_irq_disable();
+ local_fiq_disable();
+ ret = cpu_pm_enter();
+ if (!ret) {
+ ret = cpu_suspend((unsigned long)cache_disable, nocache_trampoline);
+ cpu_pm_exit();
+ }
+ local_fiq_enable();
+ local_irq_enable();
+ if (ret)
+ pr_err("%s returned %d\n", __func__, ret);
+ return ret;
+}
+
+#endif
+
struct sync_struct mcpm_sync;
/*