Re: [RFC PATCH 3/3] ARM: vfp: Use cpu pm notifiers to save vfp state

From: Colin Cross
Date: Sun Feb 13 2011 - 16:25:19 EST


On Fri, Feb 11, 2011 at 11:50 AM, Colin Cross <ccross@xxxxxxxxxxx> wrote:
>> Something like below (untested):
>>
>>        if (last_VFP_context[cpu]) {
>>                vfp_save_state(last_VFP_context[cpu], fpexc);
>>                /* force a reload when coming back from idle */
>>                last_VFP_context[cpu] = NULL;
>>                fmxr(FPEXC, fpexc & ~FPEXC_EN);
>>        }
One more fix is necessary, the VFP will usually not be enabled when
this is called. The VFP needs to be enabled before vfp_save_state,
and then disabled after.

>        /* save state for resumption */
>        if (last_VFP_context[ti->cpu]) {
>                printk(KERN_DEBUG "%s: saving vfp state\n", __func__);
>                vfp_save_state(last_VFP_context[ti->cpu], fpexc);
>
>                /* disable, just in case */
>                fmxr(FPEXC, fpexc & ~FPEXC_EN);
>        }
Same fix is needed here.
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