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author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-05 09:03:46 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-05 09:03:46 -0700 |
commit | cdd854bc42b5e6c79bbbc40c6600d995ffe6e747 (patch) | |
tree | 18c4dcc07bbb8aeb2b23bc812cd60cc293f36cd8 /arch/powerpc/kernel/machine_kexec_64.c | |
parent | bbc4fd12a635492ad9d12bb418124fa2d5f0d734 (diff) | |
parent | 42a0ae2282b512d1a8f6f020327f5f7b8f31a5ea (diff) | |
download | linux-cdd854bc42b5e6c79bbbc40c6600d995ffe6e747.tar.bz2 |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (79 commits)
powerpc/8xx: Add support for the MPC8xx based boards from TQC
powerpc/85xx: Introduce support for the Freescale P1022DS reference board
powerpc/85xx: Adding DTS for the STx GP3-SSA MPC8555 board
powerpc/85xx: Change deprecated binding for 85xx-based boards
powerpc/tqm85xx: add a quirk for ti1520 PCMCIA bridge
powerpc/tqm85xx: update PCI interrupt-map attribute
powerpc/mpc8308rdb: support for MPC8308RDB board from Freescale
powerpc/fsl_pci: add quirk for mpc8308 pcie bridge
powerpc/85xx: Cleanup QE initialization for MPC85xxMDS boards
powerpc/85xx: Fix booting for P1021MDS boards
powerpc/85xx: Fix SWIOTLB initalization for MPC85xxMDS boards
powerpc/85xx: kexec for SMP 85xx BookE systems
powerpc/5200/i2c: improve i2c bus error recovery
of/xilinxfb: update tft compatible versions
powerpc/fsl-diu-fb: Support setting display mode using EDID
powerpc/5121: doc/dts-bindings: update doc of FSL DIU bindings
powerpc/5121: shared DIU framebuffer support
powerpc/5121: move fsl-diu-fb.h to include/linux
powerpc/5121: fsl-diu-fb: fix issue with re-enabling DIU area descriptor
powerpc/512x: add clock structure for Video-IN (VIU) unit
...
Diffstat (limited to 'arch/powerpc/kernel/machine_kexec_64.c')
-rw-r--r-- | arch/powerpc/kernel/machine_kexec_64.c | 78 |
1 files changed, 72 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c index ed31a29c4ff7..583af70c4b14 100644 --- a/arch/powerpc/kernel/machine_kexec_64.c +++ b/arch/powerpc/kernel/machine_kexec_64.c @@ -15,6 +15,8 @@ #include <linux/thread_info.h> #include <linux/init_task.h> #include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/cpu.h> #include <asm/page.h> #include <asm/current.h> @@ -25,6 +27,7 @@ #include <asm/sections.h> /* _end */ #include <asm/prom.h> #include <asm/smp.h> +#include <asm/hw_breakpoint.h> int default_machine_kexec_prepare(struct kimage *image) { @@ -165,6 +168,7 @@ static void kexec_smp_down(void *arg) while(kexec_all_irq_disabled == 0) cpu_relax(); mb(); /* make sure all irqs are disabled before this */ + hw_breakpoint_disable(); /* * Now every CPU has IRQs off, we can clear out any pending * IPIs and be sure that no more will come in after this. @@ -180,8 +184,22 @@ static void kexec_prepare_cpus_wait(int wait_state) { int my_cpu, i, notified=-1; + hw_breakpoint_disable(); my_cpu = get_cpu(); - /* Make sure each CPU has atleast made it to the state we need */ + /* Make sure each CPU has at least made it to the state we need. + * + * FIXME: There is a (slim) chance of a problem if not all of the CPUs + * are correctly onlined. If somehow we start a CPU on boot with RTAS + * start-cpu, but somehow that CPU doesn't write callin_cpu_map[] in + * time, the boot CPU will timeout. If it does eventually execute + * stuff, the secondary will start up (paca[].cpu_start was written) and + * get into a peculiar state. If the platform supports + * smp_ops->take_timebase(), the secondary CPU will probably be spinning + * in there. If not (i.e. pseries), the secondary will continue on and + * try to online itself/idle/etc. If it survives that, we need to find + * these possible-but-not-online-but-should-be CPUs and chaperone them + * into kexec_smp_wait(). + */ for_each_online_cpu(i) { if (i == my_cpu) continue; @@ -189,9 +207,9 @@ static void kexec_prepare_cpus_wait(int wait_state) while (paca[i].kexec_state < wait_state) { barrier(); if (i != notified) { - printk( "kexec: waiting for cpu %d (physical" - " %d) to enter %i state\n", - i, paca[i].hw_cpu_id, wait_state); + printk(KERN_INFO "kexec: waiting for cpu %d " + "(physical %d) to enter %i state\n", + i, paca[i].hw_cpu_id, wait_state); notified = i; } } @@ -199,9 +217,32 @@ static void kexec_prepare_cpus_wait(int wait_state) mb(); } -static void kexec_prepare_cpus(void) +/* + * We need to make sure each present CPU is online. The next kernel will scan + * the device tree and assume primary threads are online and query secondary + * threads via RTAS to online them if required. If we don't online primary + * threads, they will be stuck. However, we also online secondary threads as we + * may be using 'cede offline'. In this case RTAS doesn't see the secondary + * threads as offline -- and again, these CPUs will be stuck. + * + * So, we online all CPUs that should be running, including secondary threads. + */ +static void wake_offline_cpus(void) { + int cpu = 0; + for_each_present_cpu(cpu) { + if (!cpu_online(cpu)) { + printk(KERN_INFO "kexec: Waking offline cpu %d.\n", + cpu); + cpu_up(cpu); + } + } +} + +static void kexec_prepare_cpus(void) +{ + wake_offline_cpus(); smp_call_function(kexec_smp_down, NULL, /* wait */0); local_irq_disable(); mb(); /* make sure IRQs are disabled before we say they are */ @@ -215,7 +256,10 @@ static void kexec_prepare_cpus(void) if (ppc_md.kexec_cpu_down) ppc_md.kexec_cpu_down(0, 0); - /* Before removing MMU mapings make sure all CPUs have entered real mode */ + /* + * Before removing MMU mappings make sure all CPUs have entered real + * mode: + */ kexec_prepare_cpus_wait(KEXEC_STATE_REAL_MODE); put_cpu(); @@ -257,6 +301,12 @@ static void kexec_prepare_cpus(void) static union thread_union kexec_stack __init_task_data = { }; +/* + * For similar reasons to the stack above, the kexecing CPU needs to be on a + * static PACA; we switch to kexec_paca. + */ +struct paca_struct kexec_paca; + /* Our assembly helper, in kexec_stub.S */ extern NORET_TYPE void kexec_sequence(void *newstack, unsigned long start, void *image, void *control, @@ -278,12 +328,28 @@ void default_machine_kexec(struct kimage *image) if (crashing_cpu == -1) kexec_prepare_cpus(); + pr_debug("kexec: Starting switchover sequence.\n"); + /* switch to a staticly allocated stack. Based on irq stack code. * XXX: the task struct will likely be invalid once we do the copy! */ kexec_stack.thread_info.task = current_thread_info()->task; kexec_stack.thread_info.flags = 0; + /* We need a static PACA, too; copy this CPU's PACA over and switch to + * it. Also poison per_cpu_offset to catch anyone using non-static + * data. + */ + memcpy(&kexec_paca, get_paca(), sizeof(struct paca_struct)); + kexec_paca.data_offset = 0xedeaddeadeeeeeeeUL; + paca = (struct paca_struct *)RELOC_HIDE(&kexec_paca, 0) - + kexec_paca.paca_index; + setup_paca(&kexec_paca); + + /* XXX: If anyone does 'dynamic lppacas' this will also need to be + * switched to a static version! + */ + /* Some things are best done in assembly. Finding globals with * a toc is easier in C, so pass in what we can. */ |