Hi Marc,

On 09/13/2016 07:00 PM, Marc Zyngier wrote:
> Argh, new version...
>
> On 13/09/16 11:39, fu....@linaro.org wrote:
>> From: Fu Wei <fu....@linaro.org>
>>
>> The patch add memory-mapped timer register support by using the information
>> provided by the new GTDT driver of ACPI.
>>
>> Signed-off-by: Fu Wei <fu....@linaro.org>
>> ---
>>  drivers/clocksource/arm_arch_timer.c | 127 
>> ++++++++++++++++++++++++++++++++++-
>>  1 file changed, 124 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/clocksource/arm_arch_timer.c 
>> b/drivers/clocksource/arm_arch_timer.c
>> index 0197ef9..d33802b 100644
>> --- a/drivers/clocksource/arm_arch_timer.c
>> +++ b/drivers/clocksource/arm_arch_timer.c
>> @@ -888,7 +888,128 @@ CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, 
>> "arm,armv7-timer-mem",
>>                     arch_timer_mem_init);
>>  
>>  #ifdef CONFIG_ACPI_GTDT
>> -/* Initialize per-processor generic timer */
>> +static struct gt_timer_data __init *arch_timer_mem_get_timer(
>> +                                            struct gt_block_data *gt_blocks)
>> +{
>> +    struct gt_block_data *gt_block = gt_blocks;
>> +    struct gt_timer_data *best_frame = NULL;
>> +    void __iomem *cntctlbase;
>> +    u32 cnttidr;
>> +    int i;
>> +
>> +    /*
>> +     * According to ARMv8 Architecture Reference Manual(ARM),
>> +     * the size of CNTCTLBase frame of memory-mapped timer
>> +     * is SZ_4K(Offset 0x000 – 0xFFF).
>> +     */
>> +    cntctlbase = ioremap(gt_block->cntctlbase_phy, SZ_4K);
>> +    if (!cntctlbase) {
>> +            pr_err("Failed to map mem timer control frame base address\n");
>> +            return NULL;
>> +    }
>> +    cnttidr = readl_relaxed(cntctlbase + CNTTIDR);
>> +
>> +    /*
>> +     * Try to find a virtual capable frame. Otherwise fall back to a
>> +     * physical capable frame.
>> +     */
>> +    for (i = 0; i < gt_block->timer_count; i++) {
>> +            int n;
>> +            u32 cntacr;
>> +
>> +            n = gt_block->timer[i].frame_nr;
>> +
>> +            /* Try enabling everything, and see what sticks */
>> +            cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
>> +                     CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
>> +            writel_relaxed(cntacr, cntctlbase + CNTACR(n));
>> +            cntacr = readl_relaxed(cntctlbase + CNTACR(n));
>> +
>> +            if ((cnttidr & CNTTIDR_VIRT(n)) &&
>> +                !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) {
>> +                    best_frame = &gt_block->timer[i];
>> +                    arch_timer_mem_use_virtual = true;
>> +                    break;
>> +            }
>> +
>> +            if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
>> +                    continue;
>> +
>> +            best_frame = &gt_block->timer[i];
>> +    }
>> +    iounmap(cntctlbase);
> As I just said in my reply to the same patch in v11, all of this is
> duplicating existing infrastructure that already exists for DT. Please
> consider decoupling the core driver code from the firmware side and make
> this reusable.

Great thanks for your help, I am working on it now.
Any suggestion for other arm_arch_timer patches?

> Thanks,
>
>       M.

-- 
Best regards,

Fu Wei
Software Engineer
Red Hat 

Reply via email to