[PATCH v5 1/4] omap: mmc: Avoid using libfdt with of-platdata

[Faiz Abbas]

Hi Tom,

On 14/05/20 8:29 pm, Tom Rini wrote:
> On Thu, May 14, 2020 at 01:49:37PM +0530, Faiz Abbas wrote:
>> Simon,
>>
>> On 05/05/20 12:20 pm, Faiz Abbas wrote:
>>> Hi,
>>>
>>> On 04/05/20 6:44 pm, Simon Glass wrote:
>>>> Hi Bart,
>>>>
>>>> On Mon, 4 May 2020 at 01:10, Bartosz Golaszewski <brgl at bgdev.pl> wrote:
>>>>>
>>>>> pt., 1 maj 2020 o 20:32 Tom Rini <trini at konsulko.com> napisał(a):
>>>>>>
>>>>>> On Thu, Apr 30, 2020 at 01:43:30PM +0200, Bartosz Golaszewski wrote:
>>>>>>> wt., 28 kwi 2020 o 09:01 Faiz Abbas <faiz_abbas at ti.com> napisał(a):
>>>>>>>>
>>>>>>>> +Bartosz
>>>>>>>>
>>>>>>>> On 28/04/20 9:47 am, Lokesh Vutla wrote:
>>>>>>>>> +Faiz,
>>>>>>>>>
>>>>>>>>> On 28/04/20 12:29 AM, Tom Rini wrote:
>>>>>>>>>> On Mon, Apr 27, 2020 at 05:33:41AM +0000, Peng Fan wrote:
>>>>>>>>>>>> Subject: [PATCH v5 1/4] omap: mmc: Avoid using libfdt with of-platdata
>>>>>>>>>>>>
...
>>>>>>>
>>>>>>> I can confirm - this *does* break the mmc boot on da850-lcdk.
>>>>>>
>>>>>> So who is going to fix the driver to unblock Simon's series?
>>>>>>
>>>>>
>>>>> Is this something that will take a lot of work? What exactly needs
>>>>> doing? I'm not sure what "use of-platdata properly" means.
>>>>
>>>> This board is defining CONFIG_SPL_OF_PLATDATA which means that device
>>>> tree is not available in SPL. Instead you need to use a C structure
>>>> created by dtoc. It basically involves creating that struct and
>>>> getting the data from that instead of calling the DT functions. I
>>>> expect it will take 2-4 hours to figure out, code and test.
>>>>
>>>> See of-plat.rst for full documentation. There are quite a few examples for mmc:
>>>>
>>>> grep PLATDATA drivers/mmc/*.c
>>>> drivers/mmc/ftsdc010_mci.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/ftsdc010_mci.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/ftsdc010_mci.c:#if !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/ftsdc010_mci.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/mxsmmc.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/mxsmmc.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/mxsmmc.c: debug("OF_PLATDATA: regs: 0x%p bw: %d clkid: %d
>>>> non_removable: %d\n",
>>>> drivers/mmc/mxsmmc.c:#if CONFIG_IS_ENABLED(OF_CONTROL) &&
>>>> !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/mxsmmc.c:#if CONFIG_IS_ENABLED(OF_CONTROL) &&
>>>> !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/omap_hsmmc.c:#if CONFIG_IS_ENABLED(OF_CONTROL) &&
>>>> !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/omap_hsmmc.c:#if CONFIG_IS_ENABLED(OF_CONTROL) &&
>>>> !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/omap_hsmmc.c:#if CONFIG_IS_ENABLED(OF_CONTROL) &&
>>>> !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/rockchip_dw_mmc.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/rockchip_dw_mmc.c:#if !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/rockchip_dw_mmc.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/rockchip_sdhci.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/rockchip_sdhci.c:#if CONFIG_IS_ENABLED(OF_PLATDATA)
>>>> drivers/mmc/rockchip_sdhci.c:#if !CONFIG_IS_ENABLED(OF_PLATDATA)
>>>>
>>
>> In all the examples above, platdata reg filed is directly being used for
>> to assign a register base address but looking at davinci platdata that is generated,
>> spl/dts/dt-platdata.c:
>>
>> static const struct dtd_simple_bus dtv_soc_at_1c00000 = {
>>         .model                  = "da850",
>>         .ranges                 = {0x0, 0x1c00000, 0x400000},
>> };
>> U_BOOT_DEVICE(soc_at_1c00000) = {
>>         .name           = "simple_bus",
>>         .platdata       = &dtv_soc_at_1c00000,
>>         .platdata_size  = sizeof(dtv_soc_at_1c00000),
>> };
>>
>> static const struct dtd_ti_da830_uart dtv_serial_at_10d000 = {
>>         .power_domains          = {0xa, 0xd},
>>         .reg                    = {0x10d000, 0x100},
>>         .reg_io_width           = 0x4,
>>         .reg_shift              = 0x2,
>> };
>> U_BOOT_DEVICE(serial_at_10d000) = {
>>         .name           = "ti_da830_uart",
>>         .platdata       = &dtv_serial_at_10d000,
>>         .platdata_size  = sizeof(dtv_serial_at_10d000),
>> };
>>
>> static const struct dtd_ti_da830_mmc dtv_mmc_at_40000 = {
>>         .bus_width              = 0x4,
>>         .cap_mmc_highspeed      = true,
>>         .cap_sd_highspeed       = true,
>>         .cd_gpios               = {0x16, 0x40, 0x1},
>>         .dma_names              = {"rx", "tx"},
>>         .dmas                   = {0x14, 0x10, 0x0, 0x14, 0x11, 0x0},
>>         .max_frequency          = 0x2faf080,
>>         .reg                    = {0x40000, 0x1000},
>> };
>> U_BOOT_DEVICE(mmc_at_40000) = {
>>         .name           = "ti_da830_mmc",
>>         .platdata       = &dtv_mmc_at_40000,
>>         .platdata_size  = sizeof(dtv_mmc_at_40000),
>> };
>>
>> I need the base address of the MMC device (dtd_ti_da830_mmc dtv_mmc_at_40000)
>> reg = 0x40000 to be translated with the simple_bus ranges above. How do I do
>> this without a device tree as there is no parent-child relationship defined
>> between the structures? Or at least that is my understanding.
>>
>> Looks like I will have to drop OF_PLATDATA and use hardcoded U_BOOT_DEVICE()
>> declarations for this.
> 
> I'm sure the TRM for those chips is readily available in public even,
> you should be able to work it out from there, yes?
> 

The problem is not getting the offset. We already know it from the device tree. The
issue is that of-platdata doesn't support address translation (yet?). Is there a
way to do this cleanly using the generated device structures of platdata? Otherwise
as I said I will need to disable OF_PLATDATA and declare static C structures in
the board file.

Thanks,
Faiz