Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753308AbcKRUEY (ORCPT ); Fri, 18 Nov 2016 15:04:24 -0500 Received: from foss.arm.com ([217.140.101.70]:58250 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752247AbcKRUEW (ORCPT ); Fri, 18 Nov 2016 15:04:22 -0500 Date: Fri, 18 Nov 2016 20:03:36 +0000 From: Mark Rutland To: fu.wei@linaro.org Cc: rjw@rjwysocki.net, lenb@kernel.org, daniel.lezcano@linaro.org, tglx@linutronix.de, marc.zyngier@arm.com, lorenzo.pieralisi@arm.com, sudeep.holla@arm.com, hanjun.guo@linaro.org, linux-arm-kernel@lists.infradead.org, linaro-acpi@lists.linaro.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, rruigrok@codeaurora.org, harba@codeaurora.org, cov@codeaurora.org, timur@codeaurora.org, graeme.gregory@linaro.org, al.stone@linaro.org, jcm@redhat.com, wei@redhat.com, arnd@arndb.de, catalin.marinas@arm.com, will.deacon@arm.com, Suravee.Suthikulpanit@amd.com, leo.duran@amd.com, wim@iguana.be, linux@roeck-us.net, linux-watchdog@vger.kernel.org, tn@semihalf.com, christoffer.dall@linaro.org, julien.grall@arm.com Subject: Re: [PATCH v16 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT Message-ID: <20161118200335.GN1197@leverpostej> References: <1479304148-2965-1-git-send-email-fu.wei@linaro.org> <1479304148-2965-11-git-send-email-fu.wei@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1479304148-2965-11-git-send-email-fu.wei@linaro.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7098 Lines: 233 On Wed, Nov 16, 2016 at 09:49:03PM +0800, fu.wei@linaro.org wrote: > From: Fu Wei > > 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 > --- > 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 >