On 2014/9/10 0:26, Catalin Marinas wrote:
On Mon, Sep 01, 2014 at 03:57:40PM +0100, Hanjun Guo wrote:
diff --git a/arch/arm64/include/asm/acenv.h b/arch/arm64/include/asm/acenv.h new file mode 100644 index 0000000..3899ee6 --- /dev/null +++ b/arch/arm64/include/asm/acenv.h @@ -0,0 +1,18 @@ +/*
- ARM64 specific ACPICA environments and implementation
- Copyright (C) 2014, Linaro Ltd.
- Author: Hanjun Guo hanjun.guo@linaro.org
- Author: Graeme Gregory graeme.gregory@linaro.org
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License version 2 as
- published by the Free Software Foundation.
- */
+#ifndef _ASM_ACENV_H +#define _ASM_ACENV_H
+#define ACPI_FLUSH_CPU_CACHE() WARN_ONCE(1, "Not currently supported on ARM64")
Does this mean that it will be supported at some point? Looking at the places where this function is called, I don't really see how this would ever work on ARM. Which means that we add such macro just to be able to compile code that would never be used on arm64. I would rather see the relevant ACPI files only compiled on x86/IA-64 rather than arm64.
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c new file mode 100644 index 0000000..9252f72 --- /dev/null +++ b/arch/arm64/kernel/acpi.c
[...]
+/*
- acpi_boot_table_init() called from setup_arch(), always.
- find RSDP and get its address, and then find XSDT
- extract all tables and checksums them all
- We can parse ACPI boot-time tables such as MADT after
- this function is called.
- */
+void __init acpi_boot_table_init(void) +{
- /* If acpi_disabled, bail out */
- if (acpi_disabled)
return;
So at this point, there wouldn't be anything yet to set acpi_disabled to 1, unless !CONFIG_ACPI.
- /* Initialize the ACPI boot-time table parser. */
- if (acpi_table_init())
disable_acpi();
Do you need anything more to add to this function later? Otherwise, just call it in setup_arch() directly (maybe dependent on IS_ENABLED(CONFIG_ACPI) or just create an equivalent dummy acpi_table_init() when not configured).
We add FADT parse function to this function later.
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index c96172a..fb7cc0e 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -43,6 +43,7 @@ #include <linux/of_fdt.h> #include <linux/of_platform.h> #include <linux/efi.h> +#include <linux/acpi.h> #include <asm/fixmap.h> #include <asm/cpu.h> @@ -385,6 +386,9 @@ void __init setup_arch(char **cmdline_p) efi_init(); arm64_memblock_init();
- /* Parse the ACPI tables for possible boot-time configuration */
- acpi_boot_table_init();
Is there any dummy acpi_boot_table_init() when !CONFIG_ACPI? I couldn't see one in this patch, so I don't see how this would compile when ACPI is disabled.
There is a stub function in linux/acpi.h when ACPI is disabled.
Thanks Hanjun