From mboxrd@z Thu Jan 1 00:00:00 1970 From: robherring2@gmail.com (Rob Herring) Date: Wed, 27 Mar 2013 11:38:18 -0500 Subject: omap cpufreq driver in multi-platform kernels In-Reply-To: <20130327133220.GA30868@kahuna> References: <5152503C.2050503@gmail.com> <20130327133220.GA30868@kahuna> Message-ID: <5153207A.4050109@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 03/27/2013 08:32 AM, Nishanth Menon wrote: > On 02:23-20130327, Paul Walmsley wrote: >> Hi >> >> On Tue, 26 Mar 2013, Rob Herring wrote: >> >>> The omap cpufreq driver causes problems in multi-platform kernels >>> because it unconditionally registers with the cpufreq core and does not >>> check sufficiently that it is running on an omap platform. So on a >>> kernel with highbank and omap drivers booted on highbank, the >>> cpufreq-cpu0 driver fails to init. Any suggestions for how to fix? For >>> DT this could just be several of_machine_is_compatible checks, but I'm >>> not really sure for non-DT. Converting the driver to a platform driver >>> would be another option. >> >> We could move the >> >> mpu_clk = clk_get(NULL, "cpufreq_ck"); >> >> down to omap_cpufreq_init(), and bail out early if the clock alias doesn't >> exist. (Presumably we'd also want to change the clock role name if we did >> that, to something like "omap_cpufreq_ck".) >> >> Experimental patch follows, comments welcome. > We should deprecate usage on omap-cpufreq driver eventually, instead go > towards embracing the SoC generic implementation of cpufreq-cpu0 driver > IMHO. > http://marc.info/?l=linux-omap&m=136371580826031&w=2 > is the series to support cpufreq_cpu0 driver in DT based boot. > Would you think this approach is sane? That only solves the problem for DT, but not non-DT. My understanding is non-DT omap platforms will be around for some time. Rob >> >> >> - Paul >> >> From c1b4374d9cdcf59e0cbe93aa5a23335cb3e60798 Mon Sep 17 00:00:00 2001 >> From: Paul Walmsley >> Date: Tue, 26 Mar 2013 20:16:39 -0600 >> Subject: [PATCH] EXPERIMENTAL: cpufreq: avoid loading the OMAP driver on >> non-OMAP multiplatform targets >> >> etc. etc. >> --- >> arch/arm/mach-omap2/cclock2420_data.c | 2 +- >> arch/arm/mach-omap2/cclock2430_data.c | 2 +- >> arch/arm/mach-omap2/cclock3xxx_data.c | 2 +- >> arch/arm/mach-omap2/cclock44xx_data.c | 2 +- >> drivers/cpufreq/omap-cpufreq.c | 8 ++++---- >> 5 files changed, 8 insertions(+), 8 deletions(-) >> >> diff --git a/arch/arm/mach-omap2/cclock2420_data.c b/arch/arm/mach-omap2/cclock2420_data.c >> index 0f0a97c..d4316e9 100644 >> --- a/arch/arm/mach-omap2/cclock2420_data.c >> +++ b/arch/arm/mach-omap2/cclock2420_data.c >> @@ -1885,7 +1885,7 @@ static struct omap_clk omap2420_clks[] = { >> CLK(NULL, "timer_32k_ck", &func_32k_ck, CK_242X), >> CLK(NULL, "timer_sys_ck", &sys_ck, CK_242X), >> CLK(NULL, "timer_ext_ck", &alt_ck, CK_242X), >> - CLK(NULL, "cpufreq_ck", &virt_prcm_set, CK_242X), >> + CLK(NULL, "omap_cpufreq_ck", &virt_prcm_set, CK_242X), >> }; >> >> >> diff --git a/arch/arm/mach-omap2/cclock2430_data.c b/arch/arm/mach-omap2/cclock2430_data.c >> index aed8f74..7c855b9 100644 >> --- a/arch/arm/mach-omap2/cclock2430_data.c >> +++ b/arch/arm/mach-omap2/cclock2430_data.c >> @@ -2001,7 +2001,7 @@ static struct omap_clk omap2430_clks[] = { >> CLK(NULL, "timer_32k_ck", &func_32k_ck, CK_243X), >> CLK(NULL, "timer_sys_ck", &sys_ck, CK_243X), >> CLK(NULL, "timer_ext_ck", &alt_ck, CK_243X), >> - CLK(NULL, "cpufreq_ck", &virt_prcm_set, CK_243X), >> + CLK(NULL, "omap_cpufreq_ck", &virt_prcm_set, CK_243X), >> }; >> >> static const char *enable_init_clks[] = { >> diff --git a/arch/arm/mach-omap2/cclock3xxx_data.c b/arch/arm/mach-omap2/cclock3xxx_data.c >> index 4579c3c..17dd82c 100644 >> --- a/arch/arm/mach-omap2/cclock3xxx_data.c >> +++ b/arch/arm/mach-omap2/cclock3xxx_data.c >> @@ -3501,7 +3501,7 @@ static struct omap_clk omap3xxx_clks[] = { >> CLK(NULL, "uart4_ick", &uart4_ick_am35xx, CK_AM35XX), >> CLK(NULL, "timer_32k_ck", &omap_32k_fck, CK_3XXX), >> CLK(NULL, "timer_sys_ck", &sys_ck, CK_3XXX), >> - CLK(NULL, "cpufreq_ck", &dpll1_ck, CK_3XXX), >> + CLK(NULL, "omap_cpufreq_ck", &dpll1_ck, CK_3XXX), >> }; >> >> static const char *enable_init_clks[] = { >> diff --git a/arch/arm/mach-omap2/cclock44xx_data.c b/arch/arm/mach-omap2/cclock44xx_data.c >> index 3d58f33..66b85e5 100644 >> --- a/arch/arm/mach-omap2/cclock44xx_data.c >> +++ b/arch/arm/mach-omap2/cclock44xx_data.c >> @@ -1660,7 +1660,7 @@ static struct omap_clk omap44xx_clks[] = { >> CLK("4013a000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X), >> CLK("4013c000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X), >> CLK("4013e000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X), >> - CLK(NULL, "cpufreq_ck", &dpll_mpu_ck, CK_443X), >> + CLK(NULL, "omap_cpufreq_ck", &dpll_mpu_ck, CK_443X), >> }; >> >> int __init omap4xxx_clk_init(void) >> diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c >> index 9128c07..d46caa5 100644 >> --- a/drivers/cpufreq/omap-cpufreq.c >> +++ b/drivers/cpufreq/omap-cpufreq.c >> @@ -175,10 +175,6 @@ static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) >> { >> int result = 0; >> >> - mpu_clk = clk_get(NULL, "cpufreq_ck"); >> - if (IS_ERR(mpu_clk)) >> - return PTR_ERR(mpu_clk); >> - >> if (policy->cpu >= NR_CPUS) { >> result = -EINVAL; >> goto fail_ck; >> @@ -254,6 +250,10 @@ static struct cpufreq_driver omap_driver = { >> >> static int __init omap_cpufreq_init(void) >> { >> + mpu_clk = clk_get(NULL, "omap_cpufreq_ck"); >> + if (IS_ERR(mpu_clk)) >> + return PTR_ERR(mpu_clk); >> + >> mpu_dev = get_cpu_device(0); >> if (!mpu_dev) { >> pr_warning("%s: unable to get the mpu device\n", __func__); >> -- >> 1.7.10.4 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pm" in >> the body of a message to majordomo at vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >