[U-Boot] [PATCH] arm: socfpga: Actually enable L2 cache

[Stefan Roese <sr@denx.de>]

On 19.12.2015 17:31, Marek Vasut wrote:
> On Saturday, December 19, 2015 at 11:03:45 AM, Stefan Roese wrote:
>> On 19.12.2015 06:58, Marek Vasut wrote:
>>> The L2 cache was never enabled in the v7_outer_cache_enable(), fix
>>> this and enable the L2 cache.
>>>
>>> Signed-off-by: Marek Vasut <marex@denx.de>
>>> Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
>>> Cc: Chin Liang See <clsee@altera.com>
>>> ---
>>>
>>>    arch/arm/mach-socfpga/misc.c | 7 +++++--
>>>    1 file changed, 5 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/arch/arm/mach-socfpga/misc.c b/arch/arm/mach-socfpga/misc.c
>>> index b110f5b..621f5d9 100644
>>> --- a/arch/arm/mach-socfpga/misc.c
>>> +++ b/arch/arm/mach-socfpga/misc.c
>>> @@ -54,14 +54,17 @@ void enable_caches(void)
>>>
>>>    void v7_outer_cache_enable(void)
>>>    {
>>>
>>> -	/* disable the L2 cache */
>>> -	writel(0, &pl310->pl310_ctrl);
>>> +	/* Disable the L2 cache */
>>> +	clrbits_le32(&pl310->pl310_ctrl, L2X0_CTRL_EN);
>>>
>>>    	/* enable BRESP, instruction and data prefetch, full line of zeroes */
>>>    	setbits_le32(&pl310->pl310_aux_ctrl,
>>>    	
>>>    		     L310_AUX_CTRL_DATA_PREFETCH_MASK |
>>>    		     L310_AUX_CTRL_INST_PREFETCH_MASK |
>>>    		     L310_SHARED_ATT_OVERRIDE_ENABLE);
>>>
>>> +
>>> +	/* Enable the L2 cache */
>>> +	setbits_le32(&pl310->pl310_ctrl, L2X0_CTRL_EN);
>>
>> Thanks Marek. I would be interested in some number here. Do you see
>> a bigger change in the performance (ethernet driver or dhrystone)
>> by enabling the L2 cache?
>
> Neither, but I didn't see any improvement on MX6 when I enabled L2 either.

Then my feeling is, that some other configuration is needed to
effectively enable the L2 cache on those platforms. Sorry, but
I have no clear suggestions right now. Other than to look at
Linux for the L2 cache enabling.

Thanks,
Stefan