[U-Boot] [PATCH v2 22/22] x86: Add support for Intel Minnowboard Max

Bin Meng bmeng.cn at gmail.com
Wed May 27 07:19:56 CEST 2015


Hi Simon,

On Wed, May 27, 2015 at 5:37 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi Andrew,
>
> On 26 May 2015 at 13:52, Andrew Bradford <andrew at bradfordembedded.com> wrote:
>> Hi Simon and Bin (sorry for bringing this back from the dead),
>>
>> But I have a question about fsp_configs.c down below:
>>
>> On 01/27 22:13, Simon Glass wrote:
>> ------------->8---------------
>>> diff --git a/arch/x86/cpu/baytrail/fsp_configs.c b/arch/x86/cpu/baytrail/fsp_configs.c
>>> new file mode 100644
>>> index 0000000..86b6926
>>> --- /dev/null
>>> +++ b/arch/x86/cpu/baytrail/fsp_configs.c
>>> @@ -0,0 +1,156 @@
>>> +/*
>>> + * Copyright (C) 2013, Intel Corporation
>>> + * Copyright (C) 2014, Bin Meng <bmeng.cn at gmail.com>
>>> + *
>>> + * SPDX-License-Identifier:  Intel
>>> + */
>>> +
>>> +#include <common.h>
>>> +#include <asm/arch/fsp/azalia.h>
>>> +#include <asm/fsp/fsp_support.h>
>>> +
>>> +/* ALC262 Verb Table - 10EC0262 */
>>> +static const uint32_t verb_table_data13[] = {
>>> +     /* Pin Complex (NID 0x11) */
>>> +     0x01171cf0,
>>> +     0x01171d11,
>>> +     0x01171e11,
>>> +     0x01171f41,
>>> +     /* Pin Complex (NID 0x12) */
>>> +     0x01271cf0,
>>> +     0x01271d11,
>>> +     0x01271e11,
>>> +     0x01271f41,
>>> +     /* Pin Complex (NID 0x14) */
>>> +     0x01471c10,
>>> +     0x01471d40,
>>> +     0x01471e01,
>>> +     0x01471f01,
>>> +     /* Pin Complex (NID 0x15) */
>>> +     0x01571cf0,
>>> +     0x01571d11,
>>> +     0x01571e11,
>>> +     0x01571f41,
>>> +     /* Pin Complex (NID 0x16) */
>>> +     0x01671cf0,
>>> +     0x01671d11,
>>> +     0x01671e11,
>>> +     0x01671f41,
>>> +     /* Pin Complex (NID 0x18) */
>>> +     0x01871c20,
>>> +     0x01871d98,
>>> +     0x01871ea1,
>>> +     0x01871f01,
>>> +     /* Pin Complex (NID 0x19) */
>>> +     0x01971c21,
>>> +     0x01971d98,
>>> +     0x01971ea1,
>>> +     0x01971f02,
>>> +     /* Pin Complex (NID 0x1A) */
>>> +     0x01a71c2f,
>>> +     0x01a71d30,
>>> +     0x01a71e81,
>>> +     0x01a71f01,
>>> +     /* Pin Complex */
>>> +     0x01b71c1f,
>>> +     0x01b71d40,
>>> +     0x01b71e21,
>>> +     0x01b71f02,
>>> +     /* Pin Complex */
>>> +     0x01c71cf0,
>>> +     0x01c71d11,
>>> +     0x01c71e11,
>>> +     0x01c71f41,
>>> +     /* Pin Complex */
>>> +     0x01d71c01,
>>> +     0x01d71dc6,
>>> +     0x01d71e14,
>>> +     0x01d71f40,
>>> +     /* Pin Complex */
>>> +     0x01e71cf0,
>>> +     0x01e71d11,
>>> +     0x01e71e11,
>>> +     0x01e71f41,
>>> +     /* Pin Complex */
>>> +     0x01f71cf0,
>>> +     0x01f71d11,
>>> +     0x01f71e11,
>>> +     0x01f71f41,
>>> +};
>>> +
>>> +/*
>>> + * This needs to be in ROM since if we put it in CAR, FSP init loses it when
>>> + * it drops CAR.
>>> + *
>>> + * TODO(sjg at chromium.org): Move to device tree when FSP allows it
>>> + *
>>> + * VerbTable: (RealTek ALC262)
>>> + * Revision ID = 0xFF, support all steps
>>> + * Codec Verb Table For AZALIA
>>> + * Codec Address: CAd value (0/1/2)
>>> + * Codec Vendor: 0x10EC0262
>>> + */
>>> +static const struct pch_azalia_verb_table azalia_verb_table[] = {
>>> +     {
>>> +             {
>>> +                     0x10ec0262,
>>> +                     0x0000,
>>> +                     0xff,
>>> +                     0x01,
>>> +                     0x000b,
>>> +                     0x0002,
>>> +             },
>>> +             verb_table_data13
>>> +     }
>>> +};
>>> +
>>> +const struct pch_azalia_config azalia_config = {
>>> +     .pme_enable = 1,
>>> +     .docking_supported = 1,
>>> +     .docking_attached = 0,
>>> +     .hdmi_codec_enable = 1,
>>> +     .azalia_v_ci_enable = 1,
>>> +     .rsvdbits = 0,
>>> +     .azalia_verb_table_num = 1,
>>> +     .azalia_verb_table = azalia_verb_table,
>>> +     .reset_wait_timer_us = 300
>>> +};
>>> +
>>> +void update_fsp_upd(struct upd_region *fsp_upd)
>>> +{
>>> +     struct memory_down_data *mem;
>>> +
>>> +     /*
>>> +      * Configure everything here to avoid the poor hard-pressed user
>>> +      * needing to run Intel's binary configuration tool. It may also allow
>>> +      * us to support the 1GB single core variant easily.
>>> +      *
>>> +      * TODO(sjg at chromium.org): Move to device tree
>>> +      */
>>> +     fsp_upd->mrc_init_tseg_size = 8;
>>> +     fsp_upd->mrc_init_mmio_size = 0x800;
>>> +     fsp_upd->emmc_boot_mode = 0xff;
>>> +     fsp_upd->enable_sdio = 1;
>>> +     fsp_upd->enable_sdcard = 1;
>>> +     fsp_upd->enable_hsuart0 = 1;
>>> +     fsp_upd->azalia_config_ptr = (uint32_t)&azalia_config;
>>> +     fsp_upd->enable_i2_c0 = 0;
>>> +     fsp_upd->enable_i2_c2 = 0;
>>> +     fsp_upd->enable_i2_c3 = 0;
>>> +     fsp_upd->enable_i2_c4 = 0;
>>> +     fsp_upd->enable_xhci = 0;
>>> +     fsp_upd->igd_render_standby = 1;
>>> +
>>> +     mem = &fsp_upd->memory_params;
>>> +     mem->enable_memory_down = 1;
>>> +     mem->dram_speed = 1;
>>> +     mem->dimm_width = 1;
>>> +     mem->dimm_density = 2;
>>> +     mem->dimm_tcl = 0xb;
>>> +     mem->dimm_trpt_rcd = 0xb;
>>> +     mem->dimm_twr = 0xc;
>>> +     mem->dimm_twtr = 6;
>>> +     mem->dimm_trrd = 6;
>>> +     mem->dimm_trtp = 6;
>>> +     mem->dimm_tfaw = 0x14;
>>> +}
>>
>> I am trying to move this fsp upd to use device tree as I am trying to
>> create a patch set to add the Intel Valley Island E38xx board (which
>> uses a SODIMM rather than memory down).  In doing so, I've found that
>> global data doesn't seem to be available when update_fsp_upd() is called
>> and generally it seems that gd->fdt_blob is used to get a reference to
>> the flattened device tree.
>>
>> I'm not super familiar with device tree, but I was attempting to use
>> fdtdec_next_compatible(gd->fdt_blob, 0, COMPAT_INTEL_BAYTRAIL_FSP) in a
>> similar way that Quark does in my patchset (I've properly created the
>> COMPAT_INTEL_BAYTRAIL_FSP define and some device tree nodes in my dts
>> file).  When I call fdtdec_next_compatible() the board does something
>> which I'm unable to debug (Valley Island does not have the early UART
>> pins connected so I have no early UART capability) but things just seem
>> to stop.
>>
>> In manually tracing the calls which lead to update_fsp_upd(), it seems
>> that we haven't yet set up global data, so it makes sense that I can't
>> reference it.  But the device tree should be available in NOR flash or
>> in some other way which we can access in order to get the FSP UPD
>> settings.
>>
>> Is there a simple way to access the device tree while it's still in NOR
>> flash so I can avoid using gd?  Or can global data be setup prior to
>> calling update_fsp_upd() (I believe we're still in CAR at this point)?
>> Or am I misunderstanding something basic here?
>>
>> Did you have a rough outline of how this could be moved to device tree?
>
> This is a bit tricky. I would like to move fsp_init() later in the
> init sequence (e.g. to board_init_f()). See this TODO in the code:
>
> /*
> * TODO:
> *
> * According to FSP architecture spec, the fsp_init() will not return
> * to its caller, instead it requires the bootloader to provide a
> * so-called continuation function to pass into the FSP as a parameter
> * of fsp_init, and fsp_init() will call that continuation function
> * directly.
> *
> * The call to fsp_init() may need to be moved out of the car_init()
> * to cpu_init_f() with the help of some inline assembly codes.
> * Note there is another issue that fsp_init() will setup another stack
> * using the fsp_init parameter stack_top after DRAM is initialized,
> * which means any data on the previous stack (on the CAR) gets lost
> * (ie: U-Boot global_data). FSP is supposed to support such scenario,
> * however it does not work. This should be revisited in the future.
> */
>
> The primary issues are:
> 1. The need to recover the global_data
> 2. The need to change to a new stack
>
> Re 1, my reading of the HOB stuff is that it is supposed to provide
> you with a pointer to the CAR RAM (all ~128KB of it) so that you can
> go back and find your old stack (and in our case, global_data).
>
> Bin mentioned that this doesn't work - his is the comment above after
> I asked him about it.
>
> But if it could be made to work, then we could delay the init.
>
> Re 2, U-Boot expects to change to a new stack when it wants to, which
> is at the boundary of board_init_f() and board_init_r(). The Intel FSP
> should not mandate a stack change over a C function call. IMO that is
> just bad design. Dealing with it is not very easy, but one option is
> to run with the new stack for the rest of the board_init_f() sequence
> and then change stack again at the end of the sequence. Ick.
>
> To specifically address your problem, global_data is not available
> until board_init_f() is called, and the device tree comes into
> existence soon after. We could hack around it - e.g. with microcode we
> find it in the device tree and stick a pointer to it in a special
> place. But the real solution is to figure out how to move this
> fsp_init() stuff to later in the sequence. For non-FSP boards we don't
> have this problem - e.g. ivybridge does RAM init long after we have
> global_data and device tree. Note it is still running from flash at
> this point, but CAR is set up and that is where global_data resides.
>
> I'm interested to hear what you figure out.
>

I just noticed that Intel has released FSP specification v1.1 [1] in
April. After a rough read of the 1.1 spec, it looks to me that Intel
changed the fsp_init() design by breaking it down into 3 sub-routines:
FspMemoryInit(), TempRamExit() and FspSiliconInit(). I feel this might
be more logical to adapt U-Boot, but again I am not sure if the stack
migration stuff is still there. So far I don't see any new FSP
releases using the 1.1 spec.

[1] https://www-ssl.intel.com/content/www/us/en/embedded/software/fsp/fsp-architecture-spec-v1-1.html

Regards,
Bin


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