When system supporting both DT and ACPI but firmware providing no dtb, we can use this linux,uefi-stub-generated-dtb property to let kernel know that we can try ACPI configuration data even if no "acpi=force" is passed in early parameters.
CC: Mark Rutland mark.rutland@arm.com CC: Jonathan Corbet corbet@lwn.net CC: Catalin Marinas catalin.marinas@arm.com CC: Will Deacon will.deacon@arm.com CC: Leif Lindholm leif.lindholm@linaro.org CC: Grant Likely grant.likely@linaro.org CC: Matt Fleming matt.fleming@intel.com Signed-off-by: Hanjun Guo hanjun.guo@linaro.org --- Documentation/arm/uefi.txt | 3 +++ arch/arm64/include/asm/acpi.h | 1 + arch/arm64/kernel/setup.c | 30 ++++++++++++++++++++++++++++++ drivers/firmware/efi/libstub/fdt.c | 8 ++++++++ 4 files changed, 42 insertions(+)
diff --git a/Documentation/arm/uefi.txt b/Documentation/arm/uefi.txt index d60030a..5f86eae 100644 --- a/Documentation/arm/uefi.txt +++ b/Documentation/arm/uefi.txt @@ -60,5 +60,8 @@ linux,uefi-mmap-desc-ver | 32-bit | Version of the mmap descriptor format. -------------------------------------------------------------------------------- linux,uefi-stub-kern-ver | string | Copy of linux_banner from build. -------------------------------------------------------------------------------- +linux,uefi-stub-generated-dtb | bool | Indication for no DTB provided by + | | firmware. +--------------------------------------------------------------------------------
For verbose debug messages, specify 'uefi_debug' on the kernel command line. diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index 496c33b..9fcf632 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -49,6 +49,7 @@ static inline void arch_fix_phys_package_id(int num, u32 slot) { }
#else static inline void disable_acpi(void) { } +static inline void enable_acpi(void) { } #endif /* CONFIG_ACPI */
#endif /*_ASM_ACPI_H*/ diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index fc4fb7b..510a681 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -371,6 +371,29 @@ static void __init request_standard_resources(void) } }
+static int __init dt_scan_chosen(unsigned long node, const char *uname, + int depth, void *data) +{ + const char *p; + + if (depth != 1 || !data || (strcmp(uname, "chosen") != 0)) + return 0; + + p = of_get_flat_dt_prop(node, "linux,uefi-stub-generated-dtb", NULL); + *(bool *)data = p ? true : false; + + return 1; +} + +static bool __init is_uefi_stub_generated_dtb(void) +{ + bool flag = false; + + of_scan_flat_dt(dt_scan_chosen, &flag); + + return flag; +} + u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
void __init setup_arch(char **cmdline_p) @@ -399,6 +422,13 @@ void __init setup_arch(char **cmdline_p) parse_early_param();
/* + * If no dtb provided by firmware, enable ACPI and give system a + * chance to boot with ACPI configuration data + */ + if (is_uefi_stub_generated_dtb() && acpi_disabled) + enable_acpi(); + + /* * Unmask asynchronous aborts after bringing up possible earlycon. * (Report possible System Errors once we can report this occurred) */ diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c index c846a96..3777d50 100644 --- a/drivers/firmware/efi/libstub/fdt.c +++ b/drivers/firmware/efi/libstub/fdt.c @@ -154,6 +154,14 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt, if (status) goto fdt_set_fail;
+ /* Add a property to show the dtb is generated by uefi stub */ + if (!orig_fdt) { + status = fdt_setprop(fdt, node, + "linux,uefi-stub-generated-dtb", NULL, 0); + if (status) + goto fdt_set_fail; + } + return EFI_SUCCESS;
fdt_set_fail: