diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/arm/firmware.txt | 88 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/arm/samsung-boards.txt | 10 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/misc/smc.txt | 14 |
3 files changed, 112 insertions, 0 deletions
diff --git a/Documentation/arm/firmware.txt b/Documentation/arm/firmware.txt new file mode 100644 index 000000000000..c2e468fe7b0b --- /dev/null +++ b/Documentation/arm/firmware.txt @@ -0,0 +1,88 @@ +Interface for registering and calling firmware-specific operations for ARM. +---- +Written by Tomasz Figa <t.figa@samsung.com> + +Some boards are running with secure firmware running in TrustZone secure +world, which changes the way some things have to be initialized. This makes +a need to provide an interface for such platforms to specify available firmware +operations and call them when needed. + +Firmware operations can be specified using struct firmware_ops + + struct firmware_ops { + /* + * Enters CPU idle mode + */ + int (*do_idle)(void); + /* + * Sets boot address of specified physical CPU + */ + int (*set_cpu_boot_addr)(int cpu, unsigned long boot_addr); + /* + * Boots specified physical CPU + */ + int (*cpu_boot)(int cpu); + /* + * Initializes L2 cache + */ + int (*l2x0_init)(void); + }; + +and then registered with register_firmware_ops function + + void register_firmware_ops(const struct firmware_ops *ops) + +the ops pointer must be non-NULL. + +There is a default, empty set of operations provided, so there is no need to +set anything if platform does not require firmware operations. + +To call a firmware operation, a helper macro is provided + + #define call_firmware_op(op, ...) \ + ((firmware_ops->op) ? firmware_ops->op(__VA_ARGS__) : (-ENOSYS)) + +the macro checks if the operation is provided and calls it or otherwise returns +-ENOSYS to signal that given operation is not available (for example, to allow +fallback to legacy operation). + +Example of registering firmware operations: + + /* board file */ + + static int platformX_do_idle(void) + { + /* tell platformX firmware to enter idle */ + return 0; + } + + static int platformX_cpu_boot(int i) + { + /* tell platformX firmware to boot CPU i */ + return 0; + } + + static const struct firmware_ops platformX_firmware_ops = { + .do_idle = exynos_do_idle, + .cpu_boot = exynos_cpu_boot, + /* other operations not available on platformX */ + }; + + /* init_early callback of machine descriptor */ + static void __init board_init_early(void) + { + register_firmware_ops(&platformX_firmware_ops); + } + +Example of using a firmware operation: + + /* some platform code, e.g. SMP initialization */ + + __raw_writel(virt_to_phys(exynos4_secondary_startup), + CPU1_BOOT_REG); + + /* Call Exynos specific smc call */ + if (call_firmware_op(cpu_boot, cpu) == -ENOSYS) + cpu_boot_legacy(...); /* Try legacy way */ + + gic_raise_softirq(cpumask_of(cpu), 1); diff --git a/Documentation/devicetree/bindings/arm/samsung-boards.txt b/Documentation/devicetree/bindings/arm/samsung-boards.txt index 0bf68be56fd1..2168ed31e1b0 100644 --- a/Documentation/devicetree/bindings/arm/samsung-boards.txt +++ b/Documentation/devicetree/bindings/arm/samsung-boards.txt @@ -6,3 +6,13 @@ Required root node properties: - compatible = should be one or more of the following. (a) "samsung,smdkv310" - for Samsung's SMDKV310 eval board. (b) "samsung,exynos4210" - for boards based on Exynos4210 SoC. + +Optional: + - firmware node, specifying presence and type of secure firmware: + - compatible: only "samsung,secure-firmware" is currently supported + - reg: address of non-secure SYSRAM used for communication with firmware + + firmware@0203F000 { + compatible = "samsung,secure-firmware"; + reg = <0x0203F000 0x1000>; + }; diff --git a/Documentation/devicetree/bindings/misc/smc.txt b/Documentation/devicetree/bindings/misc/smc.txt new file mode 100644 index 000000000000..02b428136177 --- /dev/null +++ b/Documentation/devicetree/bindings/misc/smc.txt @@ -0,0 +1,14 @@ +Broadcom Secure Monitor Bounce buffer +----------------------------------------------------- +This binding defines the location of the bounce buffer +used for non-secure to secure communications. + +Required properties: +- compatible : "bcm,kona-smc" +- reg : Location and size of bounce buffer + +Example: + smc@0x3404c000 { + compatible = "bcm,bcm11351-smc", "bcm,kona-smc"; + reg = <0x3404c000 0x400>; //1 KiB in SRAM + }; |