Re: [PATCH v8 25/42] ARM: davinci: dm644x: add new clock init using common clock framework

David Lechner
2018-04-03T16:30:38Z

On 04/03/2018 05:26 AM, Sekhar Nori wrote:
> On Friday 16 March 2018 08:22 AM, David Lechner wrote:
>> +static struct resource dm644x_pll1_resources[] = {
>> + {
>> + .start = DAVINCI_PLL1_BASE,
>> + .end = DAVINCI_PLL1_BASE + SZ_4K - 1,
>
> The .end should be DAVINCI_PLL1_BASE + SZ_1K - 1, otherwise it prevents
> PLL2 from getting registered.
>
>> + .flags = IORESOURCE_MEM,
>> + },
>> +};
>> +
>> +static struct platform_device dm644x_pll1_device = {
>> + .name = "dm644x-pll1",
>> + .id = -1,
>> + .resource = dm644x_pll1_resources,
>> + .num_resources = ARRAY_SIZE(dm644x_pll1_resources),
>> +};
>> +
>> +static struct resource dm644x_pll2_resources[] = {
>> + {
>> + .start = DAVINCI_PLL2_BASE,
>> + .end = DAVINCI_PLL2_BASE + SZ_4K - 1,
>
> And this too should be fixed, else it prevents the PSC from getting
> registered.
>
>> + .flags = IORESOURCE_MEM,
>> + },
>> +};
>
> With these fixed, I still had to enable 'clk_ignore_unused' on DM644x
> EVM to get to NFS boot. I think root of the problem is that pm_runtime()
> APIs are not working in the legacy boot mode.
>
> This can be seen even on the DA850 LCDK in legacy boot. pm_genpd_summary
> in debugfs shows all domains are off and there are no devices registered
> under the "da850-psc1: emac" domain. NFS mounting still works on the
> DA850 LCDK because clk_summary shows enable and prepare count of 4 for
> emac. Not sure how that's happening. But on DM644x EVM, the emac clock
> enable count is 0.
>
> Still looking at whats going wrong here. I am testing your v8 branch
> with clk-davinci branch from clk-next merged to get the fixes Stephen made.
>

In legacy mode, genpd is not being used. I didn't see any mechanism for
genpd lookup without device tree. So, we are still relying on the
matching in arch/arm/mach-davinci/pm_domain.c.

I suspect we need to fix the clock lookups in
drivers/clk/davinci/psc-dm644x.c.

LPSC_CLKDEV2(emac_clkdev, NULL, "davinci_emac.1",
"fck", "davinci_mdio.0");

NULL might need to be changed to "fck" to be picked up by pm matching
and "davinci_emac.1" should be verified that it matches the actual EMAC
device name.