| Message ID | 1422409396-24394-1-git-send-email-wenyou.yang@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jan 28, 2015 at 09:43:16AM +0800, Wenyou Yang wrote: > -#ifdef CONFIG_AT91_SLOW_CLOCK > - /* copy slow_clock handler to SRAM, and call it */ > - memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); > -#endif > slow_clock(at91_pmc_base, at91_ramc_base[0], > at91_ramc_base[1], > at91_pm_data.memctrl); > @@ -272,6 +268,9 @@ static void __init at91_pm_sram_init(void) > sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base); > slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, false); > > + /* Copy the slow_clock handler to SRAM */ > + memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); > + Why is this code not using the fncpy() support for copying functions. Why is it not checking the return code from __arm_ioremap_exec() or gen_pool_virt_to_phys() for failure? This looks like quite a massive review failure when this code was originally merged. It needs fixing.
Hi, On 29/01/2015 at 11:28:00 +0000, Russell King - ARM Linux wrote : > On Wed, Jan 28, 2015 at 09:43:16AM +0800, Wenyou Yang wrote: > > -#ifdef CONFIG_AT91_SLOW_CLOCK > > - /* copy slow_clock handler to SRAM, and call it */ > > - memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); > > -#endif > > slow_clock(at91_pmc_base, at91_ramc_base[0], > > at91_ramc_base[1], > > at91_pm_data.memctrl); > > @@ -272,6 +268,9 @@ static void __init at91_pm_sram_init(void) > > sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base); > > slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, false); > > > > + /* Copy the slow_clock handler to SRAM */ > > + memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); > > + > > Why is this code not using the fncpy() support for copying functions. Indeed, this was done in the original version of the patch that I acked. > Why is it not checking the return code from __arm_ioremap_exec() or > gen_pool_virt_to_phys() for failure? gen_pool_virt_to_phys() will not fail as the chunk is allocated just before so it will necessarily be found in the list. We need to reintroduce a check for slow_clock != NULL before fncpy() since it is moved out of its original if block.
Hi Russell, Thank you for your review. > -----Original Message----- > From: Russell King - ARM Linux [mailto:linux@arm.linux.org.uk] > Sent: Thursday, January 29, 2015 7:28 PM > To: Yang, Wenyou > Cc: Ferre, Nicolas; linux-arm-kernel@lists.infradead.org; linux- > kernel@vger.kernel.org; alexandre.belloni@free-electrons.com; > sylvain.rochet@finsecur.com; peda@axentia.se; > sergei.shtylyov@cogentembedded.com; linux@maxim.org.za > Subject: Re: [PATCH v4 05/13] pm: at91: move the copying the sram function to > the sram initializationi phase > > On Wed, Jan 28, 2015 at 09:43:16AM +0800, Wenyou Yang wrote: > > -#ifdef CONFIG_AT91_SLOW_CLOCK > > - /* copy slow_clock handler to SRAM, and call it */ > > - memcpy(slow_clock, at91_slow_clock, > at91_slow_clock_sz); > > -#endif > > slow_clock(at91_pmc_base, at91_ramc_base[0], > > at91_ramc_base[1], > > at91_pm_data.memctrl); > > @@ -272,6 +268,9 @@ static void __init at91_pm_sram_init(void) > > sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base); > > slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, > > false); > > > > + /* Copy the slow_clock handler to SRAM */ > > + memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); > > + > > Why is this code not using the fncpy() support for copying functions. At first, used the fncpy(), but it work not well on the some chip. I will check it again. > Why is it not checking the return code from __arm_ioremap_exec() or > gen_pool_virt_to_phys() for failure? > > This looks like quite a massive review failure when this code was originally merged. > It needs fixing. I will fix it. > > -- > FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up > according to speedtest.net. Best Regards, Wenyou Yang
Hi Alexandre, > -----Original Message----- > From: Alexandre Belloni [mailto:alexandre.belloni@free-electrons.com] > Sent: Thursday, January 29, 2015 11:09 PM > To: Russell King - ARM Linux > Cc: Yang, Wenyou; Ferre, Nicolas; linux-arm-kernel@lists.infradead.org; linux- > kernel@vger.kernel.org; sylvain.rochet@finsecur.com; peda@axentia.se; > sergei.shtylyov@cogentembedded.com; linux@maxim.org.za > Subject: Re: [PATCH v4 05/13] pm: at91: move the copying the sram function to > the sram initializationi phase > > Hi, > > On 29/01/2015 at 11:28:00 +0000, Russell King - ARM Linux wrote : > > On Wed, Jan 28, 2015 at 09:43:16AM +0800, Wenyou Yang wrote: > > > -#ifdef CONFIG_AT91_SLOW_CLOCK > > > - /* copy slow_clock handler to SRAM, and call it */ > > > - memcpy(slow_clock, at91_slow_clock, > at91_slow_clock_sz); > > > -#endif > > > slow_clock(at91_pmc_base, at91_ramc_base[0], > > > at91_ramc_base[1], > > > at91_pm_data.memctrl); > > > @@ -272,6 +268,9 @@ static void __init at91_pm_sram_init(void) > > > sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base); > > > slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, > > > false); > > > > > > + /* Copy the slow_clock handler to SRAM */ > > > + memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); > > > + > > > > Why is this code not using the fncpy() support for copying functions. > > Indeed, this was done in the original version of the patch that I acked. Yes, in the original version used the fncpy(), but it works not well for some SoCs. Sorry for that, I forget to record it on the change log. > > > Why is it not checking the return code from __arm_ioremap_exec() or > > gen_pool_virt_to_phys() for failure? > > gen_pool_virt_to_phys() will not fail as the chunk is allocated just before so it will > necessarily be found in the list. > > We need to reintroduce a check for slow_clock != NULL before fncpy() since it is > moved out of its original if block. > > -- > Alexandre Belloni, Free Electrons > Embedded Linux, Kernel and Android engineering http://free-electrons.com Best Regards, Wenyou yang
On Fri, Jan 30, 2015 at 06:59:58AM +0000, Yang, Wenyou wrote: > Hi Russell, > > Thank you for your review. > > > -----Original Message----- > > From: Russell King - ARM Linux [mailto:linux@arm.linux.org.uk] > > > > On Wed, Jan 28, 2015 at 09:43:16AM +0800, Wenyou Yang wrote: > > > @@ -272,6 +268,9 @@ static void __init at91_pm_sram_init(void) > > > sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base); > > > slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, > > > false); > > > > > > + /* Copy the slow_clock handler to SRAM */ > > > + memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); > > > + > > > > Why is this code not using the fncpy() support for copying functions. > At first, used the fncpy(), but it work not well on the some chip. I > will check it again. Please report on this; why does it "work not well" ?
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c index 5dd4e41..6b08098 100644 --- a/arch/arm/mach-at91/pm.c +++ b/arch/arm/mach-at91/pm.c @@ -161,10 +161,6 @@ static int at91_pm_enter(suspend_state_t state) * turning off the main oscillator; reverse on wakeup. */ if (slow_clock) { -#ifdef CONFIG_AT91_SLOW_CLOCK - /* copy slow_clock handler to SRAM, and call it */ - memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); -#endif slow_clock(at91_pmc_base, at91_ramc_base[0], at91_ramc_base[1], at91_pm_data.memctrl); @@ -272,6 +268,9 @@ static void __init at91_pm_sram_init(void) sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base); slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, false); + /* Copy the slow_clock handler to SRAM */ + memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); + put_node: of_node_put(node); } @@ -289,7 +288,10 @@ static void __init at91_pm_init(void) if (at91_cpuidle_device.dev.platform_data) platform_device_register(&at91_cpuidle_device); - suspend_set_ops(&at91_pm_ops); + if (slow_clock) + suspend_set_ops(&at91_pm_ops); + else + pr_info("AT91: PM : Not supported, due to no sram allocated\n"); } void __init at91_rm9200_pm_init(void)