[PATCH v2 2/2] firmware: add exynos acpm driver
Tudor Ambarus
tudor.ambarus at linaro.org
Wed Oct 23 03:02:05 PDT 2024
On 10/23/24 10:53 AM, Tudor Ambarus wrote:
>
>
> On 10/23/24 10:00 AM, Krzysztof Kozlowski wrote:
>>>>>> I also cannot find any piece of code setting several of above, e.g. tx_base
>>>>> I'm not writing any SRAM configuration fields, these fields are used to
>>>>> read/retrive the channel parameters from SRAM.
>>>> I meany tx_base is always 0. Where is this property set? Ever?
>>> It's not zero. My assumption is it is set in the acpm firmware, but I
>> Where is any assignment to this member?
>
> In probe() you'll see that exynos_acpm->shmem is a pointer in SRAM to a
> struct exynos_acpm_shmem __iomem *shmem;
>
> Then in:
>
> static int exynos_acpm_chans_init()
> {
> struct exynos_acpm_shmem_chan __iomem *shmem_chans, *shmem_chan;
> struct exynos_acpm_shmem __iomem *shmem = exynos_acpm->shmem;
> ...
>
> shmem_chans = exynos_acpm_get_iomem_addr(exynos_acpm->sram_base,
> &shmem->chans);
> ...
> }
>
> shmem->chans is not initialized (or tx_base). I'm using its address in
> SRAM (&shmem->chans) which I then read it with readl_relaxed().
>
> I guess one can do the same using offsetof:
> shmem_chans = readl_realaxed(shmem + offsetof(struct exynos_acpm_shmem,
> chans));
>
I forgot to add the sram_base, the counter example should have been:
shmem_chans = exynos_acpm->sram_base +
readl_realaxed(shmem + offsetof(struct exynos_acpm_shmem,
chans));
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