[PATCH 9/9] RFC: ARM: DRA7: enable DSS_DESHDCP_CLKEN

Tomi Valkeinen tomi.valkeinen at ti.com
Mon Feb 16 00:28:36 PST 2015


On 13/02/15 17:25, Nishanth Menon wrote:
> On Fri, Feb 13, 2015 at 9:11 AM, Tomi Valkeinen <tomi.valkeinen at ti.com> wrote:
>> DRA7xx's CTRL_CORE_CONTROL_IO_2 register contains bits for various
>> subsystems, including PCIe, DCAN, QSPI and DSS. At the moment only DCAN
>> bits are used by the SW via syscon.
>>
>> For DSS there is DSS_DESHDCP_CLKEN bit. This (presumably) enables a
>> clock related to DSS's HDCP. If that clock is off, DSS module does not
>> start at all, causing OCP errors. This means that the HWMOD code is not
>> able to reset and initialize DSS.
>>
>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
>> ---
>>  arch/arm/mach-omap2/io.c | 11 +++++++++++
>>  1 file changed, 11 insertions(+)
>>
>> diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c
>> index a1bd6affb508..2206fb13f195 100644
>> --- a/arch/arm/mach-omap2/io.c
>> +++ b/arch/arm/mach-omap2/io.c
>> @@ -700,6 +700,17 @@ void __init dra7xx_init_early(void)
>>         dra7xx_hwmod_init();
>>         omap_hwmod_init_postsetup();
>>         omap_clk_soc_init = dra7xx_dt_clk_init;
>> +
>> +       if (soc_is_dra7xx()) {
> 
> Umm.. this code will only be executed for dra7xx :)

Better safe than sorry! But you're right, I'll remove the if =).

>> +               u32 v;
>> +               const u16 ctrl_core_control_io_2 = 0x558;
>> +
>> +               /* set CTRL_CORE_CONTROL_IO_2:DSS_DESHDCP_CLKEN */
>> +
>> +               v = omap_ctrl_readl(ctrl_core_control_io_2);
>> +               v |= 1;
>> +               omap_ctrl_writel(v, ctrl_core_control_io_2);
>> +       }
>>  }
>>
>>  void __init dra7xx_init_late(void)
> just my 2 cents.
> I would probably wait for control module to become syscon and probably
> model this as syscon clk - I thin we should be seeing a series
> sometime soon.

Yep, I hope Tero's work will make this patch not needed. I wanted to
include something in this series that makes the DSS usable.

 Tomi


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