diff options
Diffstat (limited to 'arch/powerpc/kexec/core_64.c')
| -rw-r--r-- | arch/powerpc/kexec/core_64.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/powerpc/kexec/core_64.c b/arch/powerpc/kexec/core_64.c index 762e4d09aacf..222aa326dace 100644 --- a/arch/powerpc/kexec/core_64.c +++ b/arch/powerpc/kexec/core_64.c @@ -17,6 +17,7 @@ #include <linux/cpu.h> #include <linux/hardirq.h> #include <linux/of.h> +#include <linux/libfdt.h> #include <asm/page.h> #include <asm/current.h> @@ -26,10 +27,12 @@ #include <asm/paca.h> #include <asm/mmu.h> #include <asm/sections.h> /* _end */ +#include <asm/setup.h> #include <asm/smp.h> #include <asm/hw_breakpoint.h> #include <asm/svm.h> #include <asm/ultravisor.h> +#include <asm/crashdump-ppc64.h> int machine_kexec_prepare(struct kimage *image) { @@ -315,6 +318,16 @@ void default_machine_kexec(struct kimage *image) if (!kdump_in_progress()) kexec_prepare_cpus(); +#ifdef CONFIG_PPC_PSERIES + /* + * This must be done after other CPUs have shut down, otherwise they + * could execute the 'scv' instruction, which is not supported with + * reloc disabled (see configure_exceptions()). + */ + if (firmware_has_feature(FW_FEATURE_SET_MODE)) + pseries_disable_reloc_on_exc(); +#endif + printk("kexec: Starting switchover sequence.\n"); /* switch to a staticly allocated stack. Based on irq stack code. @@ -419,3 +432,113 @@ static int __init export_htab_values(void) } late_initcall(export_htab_values); #endif /* CONFIG_PPC_64S_HASH_MMU */ + +#if defined(CONFIG_KEXEC_FILE) || defined(CONFIG_CRASH_DUMP) +/** + * add_node_props - Reads node properties from device node structure and add + * them to fdt. + * @fdt: Flattened device tree of the kernel + * @node_offset: offset of the node to add a property at + * @dn: device node pointer + * + * Returns 0 on success, negative errno on error. + */ +static int add_node_props(void *fdt, int node_offset, const struct device_node *dn) +{ + int ret = 0; + struct property *pp; + + if (!dn) + return -EINVAL; + + for_each_property_of_node(dn, pp) { + ret = fdt_setprop(fdt, node_offset, pp->name, pp->value, pp->length); + if (ret < 0) { + pr_err("Unable to add %s property: %s\n", pp->name, fdt_strerror(ret)); + return ret; + } + } + return ret; +} + +/** + * update_cpus_node - Update cpus node of flattened device tree using of_root + * device node. + * @fdt: Flattened device tree of the kernel. + * + * Returns 0 on success, negative errno on error. + * + * Note: expecting no subnodes under /cpus/<node> with device_type == "cpu". + * If this changes, update this function to include them. + */ +int update_cpus_node(void *fdt) +{ + int prev_node_offset; + const char *device_type; + const struct fdt_property *prop; + struct device_node *cpus_node, *dn; + int cpus_offset, cpus_subnode_offset, ret = 0; + + cpus_offset = fdt_path_offset(fdt, "/cpus"); + if (cpus_offset < 0 && cpus_offset != -FDT_ERR_NOTFOUND) { + pr_err("Malformed device tree: error reading /cpus node: %s\n", + fdt_strerror(cpus_offset)); + return cpus_offset; + } + + prev_node_offset = cpus_offset; + /* Delete sub-nodes of /cpus node with device_type == "cpu" */ + for (cpus_subnode_offset = fdt_first_subnode(fdt, cpus_offset); cpus_subnode_offset >= 0;) { + /* Ignore nodes that do not have a device_type property or device_type != "cpu" */ + prop = fdt_get_property(fdt, cpus_subnode_offset, "device_type", NULL); + if (!prop || strcmp(prop->data, "cpu")) { + prev_node_offset = cpus_subnode_offset; + goto next_node; + } + + ret = fdt_del_node(fdt, cpus_subnode_offset); + if (ret < 0) { + pr_err("Failed to delete a cpus sub-node: %s\n", fdt_strerror(ret)); + return ret; + } +next_node: + if (prev_node_offset == cpus_offset) + cpus_subnode_offset = fdt_first_subnode(fdt, cpus_offset); + else + cpus_subnode_offset = fdt_next_subnode(fdt, prev_node_offset); + } + + cpus_node = of_find_node_by_path("/cpus"); + /* Fail here to avoid kexec/kdump kernel boot hung */ + if (!cpus_node) { + pr_err("No /cpus node found\n"); + return -EINVAL; + } + + /* Add all /cpus sub-nodes of device_type == "cpu" to FDT */ + for_each_child_of_node(cpus_node, dn) { + /* Ignore device nodes that do not have a device_type property + * or device_type != "cpu". + */ + device_type = of_get_property(dn, "device_type", NULL); + if (!device_type || strcmp(device_type, "cpu")) + continue; + + cpus_subnode_offset = fdt_add_subnode(fdt, cpus_offset, dn->full_name); + if (cpus_subnode_offset < 0) { + pr_err("Unable to add %s subnode: %s\n", dn->full_name, + fdt_strerror(cpus_subnode_offset)); + ret = cpus_subnode_offset; + goto out; + } + + ret = add_node_props(fdt, cpus_subnode_offset, dn); + if (ret < 0) + goto out; + } +out: + of_node_put(cpus_node); + of_node_put(dn); + return ret; +} +#endif /* CONFIG_KEXEC_FILE || CONFIG_CRASH_DUMP */ |