Hi Bin,
On Wed, 2 Oct 2019 at 08:08, Bin Meng bmeng.cn@gmail.com wrote:
On Wed, Sep 25, 2019 at 10:13 PM Simon Glass sjg@chromium.org wrote:
Most x86 CPUs use a mechanism where the SPI flash is mapped into the very top of 32-bit address space, so that it can be executed in place and read simply by copying from memory. For an 8MB ROM the mapping starts at 0xff800000.
However some recent Intel CPUs do not use a simple 1:1 memory map. Instead the map starts at a different address and not all of the SPI flash is accessible through the map. This 'Fast SPI' feature requires that U-Boot check the location of the map. It is also possible (optionally) to read from the SPI flash using a driver.
Add support for booting from Fast SPI. The memory-mapped version is used by both TPL and SPL on apollolake.
Signed-off-by: Simon Glass sjg@chromium.org
Changes in v2:
- Rename the fast SPI headers
arch/x86/cpu/intel_common/Makefile | 1 + arch/x86/cpu/intel_common/fast_spi.c | 48 ++++++++++++++++++++++++++++ arch/x86/include/asm/spl.h | 1 + 3 files changed, 50 insertions(+) create mode 100644 arch/x86/cpu/intel_common/fast_spi.c
diff --git a/arch/x86/cpu/intel_common/Makefile b/arch/x86/cpu/intel_common/Makefile index 07f27c29ec7..2de567dd9fe 100644 --- a/arch/x86/cpu/intel_common/Makefile +++ b/arch/x86/cpu/intel_common/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_$(SPL_TPL_)X86_32BIT_INIT) += report_platform.o obj-$(CONFIG_$(SPL_TPL_)X86_32BIT_INIT) += mrc.o endif obj-y += cpu.o +obj-$(CONFIG_SPI_FLASH_INTEL_FAST) += fast_spi.o obj-y += lpc.o ifndef CONFIG_TARGET_EFI_APP obj-$(CONFIG_$(SPL_TPL_)X86_32BIT_INIT) += microcode.o diff --git a/arch/x86/cpu/intel_common/fast_spi.c b/arch/x86/cpu/intel_common/fast_spi.c new file mode 100644 index 00000000000..a7334ecf1a3 --- /dev/null +++ b/arch/x86/cpu/intel_common/fast_spi.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0 +/*
- Copyright 2019 Google LLC
- */
+#include <common.h> +#include <asm/io.h> +#include <asm/pci.h> +#include <asm/arch/fast_spi.h> +#include <asm/arch/iomap.h>
+/*
- Returns bios_start and fills in size of the BIOS region.
- */
+ulong fast_spi_get_bios_region(struct fast_spi_regs *regs, size_t *bios_size)
I suspect we need a public header file for these 2 APIs?
Yes but I've added it in a separate patch since it is apollolake-specific.
But based on your other comments I wonder if I can fix that and use the generic driver.
Regards, Simon