On Wed, Nov 16, 2016 at 09:49:03PM +0800, fu.wei@xxxxxxxxxx wrote:
> From: Fu Wei <fu.wei@xxxxxxxxxx>
>
> The patch refactor original memory-mapped timer init code:
> (1) Extract a subfunction for detecting a bast time frame:
> is_best_frame.
Please leave this logic in arch_timer_mem_init(). Pulling it out gains
us nothing, but makes the patch harder to review.
> (2) Refactor "arch_timer_mem_init", make it become a common code for
> memory-mapped timer init.
> (3) Add a new function "arch_timer_mem_of_init" for DT init.
These generally look fine.
Thanks,
Mark.
> Signed-off-by: Fu Wei <fu.wei@xxxxxxxxxx>
> ---
> drivers/clocksource/arm_arch_timer.c | 162 +++++++++++++++++++++++------------
> 1 file changed, 107 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
> index 9ddc091..0836bb9 100644
> --- a/drivers/clocksource/arm_arch_timer.c
> +++ b/drivers/clocksource/arm_arch_timer.c
> @@ -923,17 +923,35 @@ static int __init arch_timer_of_init(struct device_node *np)
> CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
> CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
>
> -static int __init arch_timer_mem_init(struct device_node *np)
> +static bool __init is_best_frame(void __iomem *cntctlbase, u32 cnttidr, int n)
> +{
> + u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT | CNTACR_RWVT |
> + CNTACR_RVOFF | CNTACR_RVCT;
> +
> + /* Try enabling everything, and see what sticks */
> + writel_relaxed(cntacr, cntctlbase + CNTACR(n));
> + cntacr = readl_relaxed(cntctlbase + CNTACR(n));
> +
> + if ((cnttidr & CNTTIDR_VIRT(n)) &&
> + !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT)))
> + arch_timer_mem_use_virtual = true;
> + else if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
> + return false;
> +
> + return true;
> +}
> +
> +static int __init arch_timer_mem_init(struct arch_timer_mem *timer_mem)
> {
> - struct device_node *frame, *best_frame = NULL;
> void __iomem *cntctlbase, *base;
> - unsigned int irq, ret = -EINVAL;
> + struct arch_timer_mem_frame *best_frame = NULL;
> + unsigned int irq;
> u32 cnttidr;
> + int i, ret;
>
> - arch_timers_present |= ARCH_TIMER_TYPE_MEM;
> - cntctlbase = of_iomap(np, 0);
> + cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size);
> if (!cntctlbase) {
> - pr_err("Can't find CNTCTLBase\n");
> + pr_err("Can't map CNTCTLBase.\n");
> return -ENXIO;
> }
>
> @@ -943,76 +961,110 @@ static int __init arch_timer_mem_init(struct device_node *np)
> * Try to find a virtual capable frame. Otherwise fall back to a
> * physical capable frame.
> */
> - for_each_available_child_of_node(np, frame) {
> - int n;
> - u32 cntacr;
> -
> - if (of_property_read_u32(frame, "frame-number", &n)) {
> - pr_err("Missing frame-number\n");
> - of_node_put(frame);
> - goto out;
> - }
> -
> - /* 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))) {
> - of_node_put(best_frame);
> - best_frame = frame;
> - arch_timer_mem_use_virtual = true;
> - break;
> + for (i = 0; i < timer_mem->num_frames; i++) {
> + if (is_best_frame(cntctlbase, cnttidr,
> + timer_mem->frame[i].frame_nr)) {
> + best_frame = &timer_mem->frame[i];
> + if (arch_timer_mem_use_virtual)
> + break;
> }
> -
> - if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
> - continue;
> -
> - of_node_put(best_frame);
> - best_frame = of_node_get(frame);
> }
> + iounmap(cntctlbase);
>
> - ret= -ENXIO;
> - base = arch_counter_base = of_iomap(best_frame, 0);
> - if (!base) {
> - pr_err("Can't map frame's registers\n");
> - goto out;
> + if (!best_frame) {
> + pr_err("Can't find frame for register\n");
> + return -EINVAL;
> }
>
> if (arch_timer_mem_use_virtual)
> - irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_VIRT_SPI);
> + irq = best_frame->virt_irq;
> else
> - irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_PHYS_SPI);
> + irq = best_frame->phys_irq;
>
> - ret = -EINVAL;
> if (!irq) {
> pr_err("Frame missing %s irq",
> arch_timer_mem_use_virtual ? "virt" : "phys");
> - goto out;
> + return -EINVAL;
> }
>
> - /*
> - * Try to determine the frequency from the device tree,
> - * if fail, get the frequency from CNTFRQ.
> - */
> - if (!arch_timer_rate &&
> - of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
> - arch_timer_detect_rate(base);
> + base = ioremap(best_frame->cntbase, best_frame->size);
> + if (!base) {
> + pr_err("Can't map frame's registers\n");
> + return -ENXIO;
> + }
> +
> + arch_timer_detect_rate(base);
>
> ret = arch_timer_mem_register(base, irq);
> - if (ret)
> + if (ret) {
> + iounmap(base);
> + return ret;
> + }
> +
> + arch_counter_base = base;
> + arch_timers_present |= ARCH_TIMER_TYPE_MEM;
> +
> + return 0;
> +}
> +
> +static int __init arch_timer_mem_of_init(struct device_node *np)
> +{
> + struct arch_timer_mem *timer_mem;
> + struct device_node *frame_node;
> + struct resource res;
> + int i, ret = -EINVAL;
> +
> + timer_mem = kzalloc(sizeof(*timer_mem), GFP_KERNEL);
> + if (!timer_mem)
> + return -ENOMEM;
> +
> + if (of_address_to_resource(np, 0, &res))
> goto out;
> + timer_mem->cntctlbase = res.start;
> + timer_mem->size = resource_size(&res);
>
> - return arch_timer_common_init();
> + i = 0;
> + for_each_available_child_of_node(np, frame_node) {
> + int n;
> + struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
> +
> + if (of_property_read_u32(frame_node, "frame-number", &n)) {
> + pr_err("Missing frame-number\n");
> + of_node_put(frame_node);
> + goto out;
> + }
> + frame->frame_nr = n;
> +
> + if (of_address_to_resource(frame_node, 0, &res)) {
> + of_node_put(frame_node);
> + goto out;
> + }
> + frame->cntbase = res.start;
> + frame->size = resource_size(&res);
> +
> + frame->virt_irq = irq_of_parse_and_map(frame_node,
> + ARCH_TIMER_VIRT_SPI);
> + frame->phys_irq = irq_of_parse_and_map(frame_node,
> + ARCH_TIMER_PHYS_SPI);
> +
> + if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
> + break;
> + }
> + timer_mem->num_frames = i;
> +
> + /* Try to determine the frequency from the device tree */
> + if (!arch_timer_rate)
> + of_property_read_u32(np, "clock-frequency", &arch_timer_rate);
> +
> + ret = arch_timer_mem_init(timer_mem);
> + if (!ret)
> + ret = arch_timer_common_init();
> out:
> - iounmap(cntctlbase);
> - of_node_put(best_frame);
> + kfree(timer_mem);
> return ret;
> }
> CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
> - arch_timer_mem_init);
> + arch_timer_mem_of_init);
>
> #ifdef CONFIG_ACPI
> static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)
> --
> 2.7.4
>
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