[U-Boot] [PATCH v3 013/108] x86: spi: Add helper functions for Intel Fast SPI

[Bin Meng <bmeng.cn@gmail.com>]

Hi Simon,

On Sun, Nov 3, 2019 at 5:04 AM Simon Glass <sjg@chromium.org> wrote:
>
> Hi Bin,
>
> On Fri, 1 Nov 2019 at 22:14, Bin Meng <bmeng.cn@gmail.com> wrote:
> >
> > On Mon, Oct 21, 2019 at 11:33 AM 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.
> > >
> > > In respect of a SPI flash driver, the actual SPI driver is ich.c - this
> > > just adds a few helper functions and definitions.
> > >
> > > This is used by Apollolake.
> > >
> > > Signed-off-by: Simon Glass <sjg@chromium.org>
> > > ---
> > >
> > > Changes in v3:
> > > - Add support for of-platdata for TPL
> > > - Add the missing header file
> > > - Change Fast-SPI driver into a helper file used by ICH SPI
> > > - Don't include write() and erase() in TPL
> > > - Merge in patch "x86: Add support for booting from Fast SPI"
> > > - Reorder file so that write() and erase() are together
> > > - Use pci_get_devfn()
> > >
> > > Changes in v2: None
> > >
> > >  arch/x86/cpu/intel_common/Makefile   |  1 +
> > >  arch/x86/cpu/intel_common/fast_spi.c | 73 ++++++++++++++++++++++++++++
> > >  arch/x86/include/asm/fast_spi.h      | 68 ++++++++++++++++++++++++++
> > >  arch/x86/include/asm/spl.h           |  1 +
> > >  4 files changed, 143 insertions(+)
> > >  create mode 100644 arch/x86/cpu/intel_common/fast_spi.c
> > >  create mode 100644 arch/x86/include/asm/fast_spi.h
> [..]
>
> > > +/* Register offsets from the MMIO region base (PCI_BASE_ADDRESS_0) */
> > > +struct fast_spi_regs {
> > > +       u32 bfp;
> > > +       u32 hsfsts_ctl;
> > > +       u32 faddr;
> > > +       u32 dlock;
> > > +
> > > +       u32 fdata[0x10];
> > > +
> > > +       u32 fracc;
> > > +       u32 freg[12];
> > > +       u32 fpr[5];
> > > +       u32 gpr0;
> > > +       u32 spare2;
> > > +       u32 sts_ctl;
> > > +       u16 preop;              /* a4 */
> >
> > I assume a4 is the offset of preop? Leaving it causes confusion and it
> > can be dropped, I think.
> >
>
> Will do.
>
> I'm rebasing on your applied patches and moving the code around to
> address Andy's comments. I'll send a new version v4 by Monday.

Or maybe you can wait until I looked at all v3 patches. I just wanted
to send a PR for a collection of good patches so far, instead of
giving Tom a huge list :)

Regards,
Bin