diff options
Diffstat (limited to 'target/linux/ipq806x/patches/0008-ARM-Introduce-CPU_METHOD_OF_DECLARE-for-cpu-hotplug-.patch')
| -rw-r--r-- | target/linux/ipq806x/patches/0008-ARM-Introduce-CPU_METHOD_OF_DECLARE-for-cpu-hotplug-.patch | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches/0008-ARM-Introduce-CPU_METHOD_OF_DECLARE-for-cpu-hotplug-.patch b/target/linux/ipq806x/patches/0008-ARM-Introduce-CPU_METHOD_OF_DECLARE-for-cpu-hotplug-.patch new file mode 100644 index 0000000000..9579ac2f63 --- /dev/null +++ b/target/linux/ipq806x/patches/0008-ARM-Introduce-CPU_METHOD_OF_DECLARE-for-cpu-hotplug-.patch @@ -0,0 +1,159 @@ +From 48f17325fef9cbebc5cb39aa78f4c1caff5d7b16 Mon Sep 17 00:00:00 2001 +From: Stephen Boyd <sboyd@codeaurora.org> +Date: Wed, 30 Oct 2013 18:21:09 -0700 +Subject: [PATCH 008/182] ARM: Introduce CPU_METHOD_OF_DECLARE() for cpu + hotplug/smp + +The goal of multi-platform kernels is to remove the need for mach +directories and machine descriptors. To further that goal, +introduce CPU_METHOD_OF_DECLARE() to allow cpu hotplug/smp +support to be separated from the machine descriptors. +Implementers should specify an enable-method property in their +cpus node and then implement a matching set of smp_ops in their +hotplug/smp code, wiring it up with the CPU_METHOD_OF_DECLARE() +macro. When the kernel is compiled we'll collect all the +enable-method smp_ops into one section for use at boot. + +At boot time we'll look for an enable-method in each cpu node and +try to match that against all known CPU enable methods in the +kernel. If there are no enable-methods in the cpu nodes we +fallback to the cpus node and try to use any enable-method found +there. If that doesn't work we fall back to the old way of using +the machine descriptor. + +Acked-by: Mark Rutland <mark.rutland@arm.com> +Cc: Russell King <linux@arm.linux.org.uk> +Cc: <devicetree@vger.kernel.org> +Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> +Signed-off-by: Kumar Gala <galak@codeaurora.org> +--- + arch/arm/include/asm/smp.h | 9 +++++++++ + arch/arm/kernel/devtree.c | 40 +++++++++++++++++++++++++++++++++++++ + include/asm-generic/vmlinux.lds.h | 10 ++++++++++ + 3 files changed, 59 insertions(+) + +diff --git a/arch/arm/include/asm/smp.h b/arch/arm/include/asm/smp.h +index 22a3b9b..772435b 100644 +--- a/arch/arm/include/asm/smp.h ++++ b/arch/arm/include/asm/smp.h +@@ -114,6 +114,15 @@ struct smp_operations { + #endif + }; + ++struct of_cpu_method { ++ const char *method; ++ struct smp_operations *ops; ++}; ++ ++#define CPU_METHOD_OF_DECLARE(name, _method, _ops) \ ++ static const struct of_cpu_method __cpu_method_of_table_##name \ ++ __used __section(__cpu_method_of_table) \ ++ = { .method = _method, .ops = _ops } + /* + * set platform specific SMP operations + */ +diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c +index f751714..c7419a5 100644 +--- a/arch/arm/kernel/devtree.c ++++ b/arch/arm/kernel/devtree.c +@@ -18,6 +18,7 @@ + #include <linux/of_fdt.h> + #include <linux/of_irq.h> + #include <linux/of_platform.h> ++#include <linux/smp.h> + + #include <asm/cputype.h> + #include <asm/setup.h> +@@ -63,6 +64,34 @@ void __init arm_dt_memblock_reserve(void) + } + } + ++#ifdef CONFIG_SMP ++extern struct of_cpu_method __cpu_method_of_table_begin[]; ++extern struct of_cpu_method __cpu_method_of_table_end[]; ++ ++static int __init set_smp_ops_by_method(struct device_node *node) ++{ ++ const char *method; ++ struct of_cpu_method *m = __cpu_method_of_table_begin; ++ ++ if (of_property_read_string(node, "enable-method", &method)) ++ return 0; ++ ++ for (; m < __cpu_method_of_table_end; m++) ++ if (!strcmp(m->method, method)) { ++ smp_set_ops(m->ops); ++ return 1; ++ } ++ ++ return 0; ++} ++#else ++static inline int set_smp_ops_by_method(struct device_node *node) ++{ ++ return 1; ++} ++#endif ++ ++ + /* + * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree + * and builds the cpu logical map array containing MPIDR values related to +@@ -79,6 +108,7 @@ void __init arm_dt_init_cpu_maps(void) + * read as 0. + */ + struct device_node *cpu, *cpus; ++ int found_method = 0; + u32 i, j, cpuidx = 1; + u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0; + +@@ -150,8 +180,18 @@ void __init arm_dt_init_cpu_maps(void) + } + + tmp_map[i] = hwid; ++ ++ if (!found_method) ++ found_method = set_smp_ops_by_method(cpu); + } + ++ /* ++ * Fallback to an enable-method in the cpus node if nothing found in ++ * a cpu node. ++ */ ++ if (!found_method) ++ set_smp_ops_by_method(cpus); ++ + if (!bootcpu_valid) { + pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n"); + return; +diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h +index bc2121f..bd02ca7 100644 +--- a/include/asm-generic/vmlinux.lds.h ++++ b/include/asm-generic/vmlinux.lds.h +@@ -167,6 +167,15 @@ + #define CLK_OF_TABLES() + #endif + ++#ifdef CONFIG_SMP ++#define CPU_METHOD_OF_TABLES() . = ALIGN(8); \ ++ VMLINUX_SYMBOL(__cpu_method_of_table_begin) = .; \ ++ *(__cpu_method_of_table) \ ++ VMLINUX_SYMBOL(__cpu_method_of_table_end) = .; ++#else ++#define CPU_METHOD_OF_TABLES() ++#endif ++ + #define KERNEL_DTB() \ + STRUCT_ALIGN(); \ + VMLINUX_SYMBOL(__dtb_start) = .; \ +@@ -491,6 +500,7 @@ + MEM_DISCARD(init.rodata) \ + CLK_OF_TABLES() \ + CLKSRC_OF_TABLES() \ ++ CPU_METHOD_OF_TABLES() \ + KERNEL_DTB() \ + IRQCHIP_OF_MATCH_TABLE() + +-- +1.7.10.4 + |