[U-Boot] [PATCH 4/7] dm: Expand the uclass for Peripheral Controller Hubs (PCH)

[Bin Meng]

Hi Simon,

On Thu, Dec 17, 2015 at 12:09 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi Bin,
>
> On 8 December 2015 at 06:23, Bin Meng <bmeng.cn at gmail.com> wrote:
>> Hi Simon,
>>
>> On Tue, Dec 1, 2015 at 12:11 PM, Simon Glass <sjg at chromium.org> wrote:
>>> A Peripheral Controller Hub is an Intel concept - it is like the peripherals
>>
>> I believe the name is Platform Controller Hub.
>>
>>> on an SoC and is often in a separate chip from the CPU. Even when it is not
>>> it is addressed and used differently. The chip is typically found on the
>>
>> "Even when it is not" (a separate chip) "it is addressed and used
>> differently"? I feel it should be "it is addressed and used the same'?
>>
>>> first PCI device.
>>
>> This indicates b.d.f = 0.0.0, but for registers like RCBA, SPI base,
>> those are actually on the LPC device (b.d.f = 0.1f.0). Maybe we can
>> say: the chip is typically found on the first PCI bus and integrates
>> multiple devices?
>>
>>>
>>> We have a very simple uclass to support PCHs. Add a few operations, such as
>>> setting up the devices on the PCH and finding the SPI controller base
>>> address. Also move it into drivers/pch/ since we will be adding a few PCH
>>> drivers.
>>>
>>> Signed-off-by: Simon Glass <sjg at chromium.org>
>>> ---
>>>
>>>  arch/x86/lib/Makefile                      |  1 -
>>>  drivers/Makefile                           |  1 +
>>>  drivers/pch/Makefile                       |  5 +++
>>>  {arch/x86/lib => drivers/pch}/pch-uclass.c | 32 +++++++++++++++
>>>  include/pch.h                              | 66 ++++++++++++++++++++++++++++++
>>>  5 files changed, 104 insertions(+), 1 deletion(-)
>>>  create mode 100644 drivers/pch/Makefile
>>>  rename {arch/x86/lib => drivers/pch}/pch-uclass.c (53%)
>>>  create mode 100644 include/pch.h
>>>
>>> diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
>>> index cd5ecb6..43792bc 100644
>>> --- a/arch/x86/lib/Makefile
>>> +++ b/arch/x86/lib/Makefile
>>> @@ -24,7 +24,6 @@ obj-$(CONFIG_I8254_TIMER) += i8254.o
>>>  ifndef CONFIG_DM_PCI
>>>  obj-$(CONFIG_PCI) += pci_type1.o
>>>  endif
>>> -obj-y  += pch-uclass.o
>>>  obj-y  += pirq_routing.o
>>>  obj-y  += relocate.o
>>>  obj-y += physmem.o
>>> diff --git a/drivers/Makefile b/drivers/Makefile
>>> index c9031f2..acc6af9 100644
>>> --- a/drivers/Makefile
>>> +++ b/drivers/Makefile
>>> @@ -51,6 +51,7 @@ obj-y += hwmon/
>>>  obj-y += misc/
>>>  obj-y += pcmcia/
>>>  obj-y += dfu/
>>> +obj-$(CONFIG_X86) += pch/
>>>  obj-y += rtc/
>>>  obj-y += sound/
>>>  obj-y += timer/
>>> diff --git a/drivers/pch/Makefile b/drivers/pch/Makefile
>>> new file mode 100644
>>> index 0000000..d69a99c
>>> --- /dev/null
>>> +++ b/drivers/pch/Makefile
>>> @@ -0,0 +1,5 @@
>>> +#
>>> +# SPDX-License-Identifier:     GPL-2.0+
>>> +#
>>> +
>>> +obj-y += pch-uclass.o
>>> diff --git a/arch/x86/lib/pch-uclass.c b/drivers/pch/pch-uclass.c
>>> similarity index 53%
>>> rename from arch/x86/lib/pch-uclass.c
>>> rename to drivers/pch/pch-uclass.c
>>> index 20dfa81..09a0107 100644
>>> --- a/arch/x86/lib/pch-uclass.c
>>> +++ b/drivers/pch/pch-uclass.c
>>> @@ -7,10 +7,42 @@
>>>
>>>  #include <common.h>
>>>  #include <dm.h>
>>> +#include <pch.h>
>>>  #include <dm/root.h>
>>>
>>>  DECLARE_GLOBAL_DATA_PTR;
>>>
>>> +int pch_init(struct udevice *dev)
>>> +{
>>> +       struct pch_ops *ops = pch_get_ops(dev);
>>> +
>>> +       if (!ops->init)
>>> +               return -ENOSYS;
>>> +
>>> +       return ops->init(dev);
>>> +}
>>> +
>>> +int pch_get_sbase(struct udevice *dev, ulong *sbasep)
>>> +{
>>> +       struct pch_ops *ops = pch_get_ops(dev);
>>> +
>>> +       *sbasep = 0;
>>> +       if (!ops->get_sbase)
>>> +               return -ENOSYS;
>>> +
>>> +       return ops->get_sbase(dev, sbasep);
>>> +}
>>> +
>>> +int pch_get_version(struct udevice *dev)
>>> +{
>>> +       struct pch_ops *ops = pch_get_ops(dev);
>>> +
>>> +       if (!ops->get_version)
>>> +               return -ENOSYS;
>>> +
>>> +       return ops->get_version(dev);
>>> +}
>>> +
>>>  static int pch_uclass_post_bind(struct udevice *bus)
>>>  {
>>>         /*
>>> diff --git a/include/pch.h b/include/pch.h
>>> new file mode 100644
>>> index 0000000..98bb5f2
>>> --- /dev/null
>>> +++ b/include/pch.h
>>> @@ -0,0 +1,66 @@
>>> +/*
>>> + * Copyright (c) 2015 Google, Inc
>>> + * Written by Simon Glass <sjg at chromium.org>
>>> + *
>>> + * SPDX-License-Identifier:    GPL-2.0+
>>> + */
>>> +
>>> +#ifndef __pch_h
>>> +#define __pch_h
>>> +
>>> +struct pch_ops {
>>> +       /**
>>> +        * init() - set up the PCH devices
>>> +        *
>>> +        * This makes sure that all the devices are ready for use. They are
>>> +        * not actually started, just set up so that they can be probed.
>>> +        */
>>> +       int (*init)(struct udevice *dev);
>>
>> Do we need create such an init op? Should this be done in the driver's
>> probe routine?
>
> The PCH is modelled in ivybridge as the device at address 0,0,0. I
> have found that we need to do the init in two stages, so this is the
> reason for the init() method. However, I am still working on
> refactoring and simplifying the code. So it is possible that at some
> point I will figure out how to remove this. But for now I cannot see
> how.
>

Does if (gd->flags & GD_FLG_RELOC) not help?

[snip]

Regards,
Bin