On Wed, Feb 25, 2015 at 04:39:45PM +0800, Hanjun Guo wrote:
From: Al Stone al.stone@linaro.org
As we want to get ACPI tables to parse and then use the information for system initialization, we should get the RSDP (Root System Description Pointer) first, it then locates Extended Root Description Table (XSDT) which contains all the 64-bit physical address that pointer to other boot-time tables.
Introduce acpi.c and its related head file in this patch to provide fundamental needs of extern variables and functions for ACPI core, and then get boot-time tables as needed.
- asm/acenv.h for arch specific ACPICA environments and implementation, It is needed unconditionally by ACPI core;
- asm/acpi.h for arch specific variables and functions needed by ACPI driver core;
- acpi.c for ARM64 related ACPI implementation for ACPI driver core;
acpi_boot_table_init() is introduced to get RSDP and boot-time tables, it will be called in setup_arch() before paging_init(), so we should use eary_memremap() mechanism here to get the RSDP and all the table pointers.
FADT Major.Minor version was introduced in ACPI 5.1, it is the same as ACPI version.
In ACPI 5.1, some major gaps are fixed for ARM, such as updates in MADT table for GIC and SMP init, without those updates, we can not get the MPIDR for SMP init, and GICv2/3 related init information, so we can't boot arm64 ACPI properly with table versions predating 5.1.
If firmware provides ACPI tables with ACPI version less than 5.1, OS has no way to retrieve the configuration data that is necessary to init SMP boot protocol and the GIC properly, so disable ACPI if we get an FADT table with version less that 5.1 when acpi_boot_table_init() called.
CC: Catalin Marinas catalin.marinas@arm.com CC: Will Deacon will.deacon@arm.com CC: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Tested-by: Suravee Suthikulpanit Suravee.Suthikulpanit@amd.com Tested-by: Yijing Wang wangyijing@huawei.com Tested-by: Mark Langsdorf mlangsdo@redhat.com Tested-by: Jon Masters jcm@redhat.com Tested-by: Timur Tabi timur@codeaurora.org Tested-by: Robert Richter rrichter@cavium.com Acked-by: Robert Richter rrichter@cavium.com Signed-off-by: Al Stone al.stone@linaro.org Signed-off-by: Graeme Gregory graeme.gregory@linaro.org Signed-off-by: Tomasz Nowicki tomasz.nowicki@linaro.org Signed-off-by: Hanjun Guo hanjun.guo@linaro.org
As long as it goes in together with later patches that adjust what's enabled by default:
Acked-by: Olof Johansson olof@lixom.net
-Olof