[PATCH v21 11/13] acpi/arm64: Add memory-mapped timer support in GTDT driver
Mark Rutland
mark.rutland at arm.com
Fri Mar 17 12:40:55 PDT 2017
Hi,
On Tue, Feb 07, 2017 at 02:50:13AM +0800, fu.wei at linaro.org wrote:
> +static int __init gtdt_parse_timer_block(struct acpi_gtdt_timer_block *block,
> + struct arch_timer_mem *data)
Please s/data/timer_mem/ here, to match the rest of the timer code.
> +{
> + int i, j;
> + struct acpi_gtdt_timer_entry *frame;
So as to make it clear what this is, and to make things a litlte simpler
below, please s/frame/gtdt_frame/ here.
> +
> + if (!block->timer_count) {
> + pr_err(FW_BUG "GT block present, but frame count is zero.");
> + return -ENODEV;
> + }
> +
> + if (block->timer_count > ARCH_TIMER_MEM_MAX_FRAMES) {
> + pr_err(FW_BUG "GT block lists %d frames, ACPI spec only allows 8\n",
> + block->timer_count);
> + return -EINVAL;
> + }
> +
> + data->cntctlbase = (phys_addr_t)block->block_address;
> + /*
> + * According to "Table * CNTCTLBase memory map" of
> + * <ARM Architecture Reference Manual> for ARMv8,
> + * The size of the CNTCTLBase frame is 4KB(Offset 0x000 – 0xFFC).
> + */
As a general thing, please cite the version of the ARM ARM you're
referring to, as over time the internal numbering (and the headings)
change.
e.g.
/*
* The CNTCTLBase frame is 4KB (register offsets 0x000 - 0xFFC).
* See ARM DDI 0487A.k_iss10775, page I1-5129, Table I1-3
* "CNTCTLBase memory map".
*/
> + data->size = SZ_4K;
> +
> + frame = (void *)block + block->timer_offset;
> + if (frame + block->timer_count != (void *)block + block->header.length)
> + return -EINVAL;
> +
> + /*
> + * Get the GT timer Frame data for every GT Block Timer
> + */
> + for (i = 0, j = 0; i < block->timer_count; i++, frame++) {
With the gtdt_frame rename as above, here we can do:
struct arch_timer_mem_frame *frame = &timer_mem->frame[j];
> + if (frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER)
> + continue;
> +
> + if (!frame->base_address || !frame->timer_interrupt)
> + return -EINVAL;
> +
> + data->frame[j].phys_irq = map_gt_gsi(frame->timer_interrupt,
> + frame->timer_flags);
... allowing us to simplify lines like this.
Thanks,
Mark.
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