| Message ID | 20161114145459.63c23391@xhacker (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Jisheng, On Monday 14 November 2016 12:24 PM, Jisheng Zhang wrote: > > On Mon, 14 Nov 2016 14:12:51 +0800 Jisheng Zhang wrote: > >> Hi Pankaj, >> <snip> >>> + * Helper API to get SCU base address >>> + * In case platform DT do not have SCU node, or iomap fails >>> + * this call will fallback and will try to map via call to >>> + * scu_a9_get_base. >>> + * This will return ownership of scu_base to the caller >>> + */ >>> +void __iomem *of_scu_get_base(void) >>> +{ >>> + unsigned long base = 0; >>> + struct device_node *np; >>> + void __iomem *scu_base; >>> + >>> + np = of_find_matching_node(NULL, scu_match); >> >> could we check np before calling of_iomap()? >> >>> + scu_base = of_iomap(np, 0); >>> + of_node_put(np); >>> + if (!scu_base) { >>> + pr_err("%s failed to map scu_base via DT\n", __func__); >> >> For non-ca5, non-ca9 based SoCs, we'll see this error msg. We understand >> what does it mean, but it may confuse normal users. In current version, >> berlin doesn't complain like this for non-ca9 SoCs > > oops, I just realized that the non-ca9 berlin arm SoC version isn't upstreamed. > Below is the draft version I planed. Basically speaking, the code tries to > find "arm,cortex-a9-scu" node from DT, if can't, we think we don't need to > worry about SCU. Is there any elegant solution for my situation? > To adopt new generic API I have submitted a patch for Berlin (along with other various platforms) here: https://patchwork.kernel.org/patch/9426457/ Please review and if possible test and let me know feedback. Thanks, Pankaj Dubey > Thanks, > Jisheng > > > ------------8<------------------- > --- a/arch/arm/mach-berlin/platsmp.c > +++ b/arch/arm/mach-berlin/platsmp.c > @@ -56,22 +56,25 @@ static void __init berlin_smp_prepare_cpus(unsigned int max_cpus) > void __iomem *vectors_base; > > np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); > - scu_base = of_iomap(np, 0); > - of_node_put(np); > - if (!scu_base) > - return; > + if (np) { > + scu_base = of_iomap(np, 0); > + of_node_put(np); > + if (!scu_base) > + return; > + scu_enable(scu_base); > + iounmap(scu_base); > + } > > np = of_find_compatible_node(NULL, NULL, "marvell,berlin-cpu-ctrl"); > cpu_ctrl = of_iomap(np, 0); > of_node_put(np); > if (!cpu_ctrl) > - goto unmap_scu; > + return; > > vectors_base = ioremap(CONFIG_VECTORS_BASE, SZ_32K); > if (!vectors_base) > - goto unmap_scu; > + return; > > - scu_enable(scu_base); > flush_cache_all(); > > /* > @@ -87,8 +90,6 @@ static void __init berlin_smp_prepare_cpus(unsigned int max_cpus) > writel(virt_to_phys(secondary_startup), vectors_base + SW_RESET_ADDR); > > iounmap(vectors_base); > -unmap_scu: > - iounmap(scu_base); > } > > static struct smp_operations berlin_smp_ops __initdata = { > > >> >>> + if (scu_a9_has_base()) { >>> + base = scu_a9_get_base(); >>> + scu_base = ioremap(base, SZ_4K); >>> + } >>> + if (!scu_base) { >>> + pr_err("%s failed to map scu_base\n", __func__); >> >> ditto >> >>> + return IOMEM_ERR_PTR(-ENOMEM); >>> + } >>> + } >>> + return scu_base; >>> +} >>> + >>> +/* >>> + * Enable SCU via mapping scu_base DT >>> + * If scu_base mapped successfully scu will be enabled and in case of >>> + * failure if will return non-zero error code >>> + */ >>> +int of_scu_enable(void) >>> +{ >>> + void __iomem *scu_base; >>> + >>> + scu_base = of_scu_get_base(); >>> + if (!IS_ERR(scu_base)) { >>> + scu_enable(scu_base); >>> + iounmap(scu_base); >>> + return 0; >>> + } >>> + return PTR_ERR(scu_base); >>> +} >>> + >>> #endif >>> >>> /* >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > > >
Hi Pankaj, On Mon, 14 Nov 2016 14:54:59 +0800 Jisheng Zhang wrote: > On Mon, 14 Nov 2016 14:12:51 +0800 Jisheng Zhang wrote: > > > Hi Pankaj, > > > > On Mon, 14 Nov 2016 10:31:56 +0530 Pankaj Dubey wrote: > > > > > Many platforms are duplicating code for enabling SCU, lets add > > > common code to enable SCU by parsing SCU device node so the duplication > > > in each platform can be avoided. > > > > > > CC: Krzysztof Kozlowski <krzk@kernel.org> > > > CC: Jisheng Zhang <jszhang@marvell.com> > > > CC: Russell King <linux@armlinux.org.uk> > > > CC: Dinh Nguyen <dinguyen@opensource.altera.com> > > > CC: Patrice Chotard <patrice.chotard@st.com> > > > CC: Linus Walleij <linus.walleij@linaro.org> > > > CC: Liviu Dudau <liviu.dudau@arm.com> > > > CC: Ray Jui <rjui@broadcom.com> > > > CC: Stephen Warren <swarren@wwwdotorg.org> > > > CC: Heiko Stuebner <heiko@sntech.de> > > > CC: Shawn Guo <shawnguo@kernel.org> > > > CC: Michal Simek <michal.simek@xilinx.com> > > > CC: Wei Xu <xuwei5@hisilicon.com> > > > CC: Andrew Lunn <andrew@lunn.ch> > > > CC: Jun Nie <jun.nie@linaro.org> > > > Suggested-by: Arnd Bergmann <arnd@arndb.de> > > > Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com> > > > --- > > > arch/arm/include/asm/smp_scu.h | 4 +++ > > > arch/arm/kernel/smp_scu.c | 56 ++++++++++++++++++++++++++++++++++++++++++ > > > 2 files changed, 60 insertions(+) > > > > > > diff --git a/arch/arm/include/asm/smp_scu.h b/arch/arm/include/asm/smp_scu.h > > > index bfe163c..fdeec07 100644 > > > --- a/arch/arm/include/asm/smp_scu.h > > > +++ b/arch/arm/include/asm/smp_scu.h > > > @@ -39,8 +39,12 @@ static inline int scu_power_mode(void __iomem *scu_base, unsigned int mode) > > > > > > #if defined(CONFIG_SMP) && defined(CONFIG_HAVE_ARM_SCU) > > > void scu_enable(void __iomem *scu_base); > > > +void __iomem *of_scu_get_base(void); > > > +int of_scu_enable(void); > > > #else > > > static inline void scu_enable(void __iomem *scu_base) {} > > > +static inline void __iomem *of_scu_get_base(void) {return NULL; } > > > +static inline int of_scu_enable(void) {return 0; } > > > #endif > > > > > > #endif > > > diff --git a/arch/arm/kernel/smp_scu.c b/arch/arm/kernel/smp_scu.c > > > index 72f9241..d0ac3ed 100644 > > > --- a/arch/arm/kernel/smp_scu.c > > > +++ b/arch/arm/kernel/smp_scu.c > > > @@ -10,6 +10,7 @@ > > > */ > > > #include <linux/init.h> > > > #include <linux/io.h> > > > +#include <linux/of_address.h> > > > > > > #include <asm/smp_plat.h> > > > #include <asm/smp_scu.h> > > > @@ -70,6 +71,61 @@ void scu_enable(void __iomem *scu_base) > > > */ > > > flush_cache_all(); > > > } > > > + > > > +static const struct of_device_id scu_match[] = { > > > + { .compatible = "arm,cortex-a9-scu", }, > > > + { .compatible = "arm,cortex-a5-scu", }, > > > + { } > > > +}; > > > + > > > +/* > > > + * Helper API to get SCU base address > > > + * In case platform DT do not have SCU node, or iomap fails > > > + * this call will fallback and will try to map via call to > > > + * scu_a9_get_base. > > > + * This will return ownership of scu_base to the caller > > > + */ > > > +void __iomem *of_scu_get_base(void) > > > +{ > > > + unsigned long base = 0; > > > + struct device_node *np; > > > + void __iomem *scu_base; > > > + > > > + np = of_find_matching_node(NULL, scu_match); > > > > could we check np before calling of_iomap()? > > > > > + scu_base = of_iomap(np, 0); > > > + of_node_put(np); > > > + if (!scu_base) { > > > + pr_err("%s failed to map scu_base via DT\n", __func__); > > > > For non-ca5, non-ca9 based SoCs, we'll see this error msg. We understand > > what does it mean, but it may confuse normal users. In current version, > > berlin doesn't complain like this for non-ca9 SoCs > > oops, I just realized that the non-ca9 berlin arm SoC version isn't upstreamed. > Below is the draft version I planed. Basically speaking, the code tries to > find "arm,cortex-a9-scu" node from DT, if can't, we think we don't need to > worry about SCU. Is there any elegant solution for my situation? I just realized that (another realized :D) we uses PSCI enable method for non-ca9 base SoCs, so "marvell,berlin-smp" enable method is only for the SoCs which have CA9 compatible SCU. Sorry for the noise, your patch looks good to me.
--- a/arch/arm/mach-berlin/platsmp.c +++ b/arch/arm/mach-berlin/platsmp.c @@ -56,22 +56,25 @@ static void __init berlin_smp_prepare_cpus(unsigned int max_cpus) void __iomem *vectors_base; np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); - scu_base = of_iomap(np, 0); - of_node_put(np); - if (!scu_base) - return; + if (np) { + scu_base = of_iomap(np, 0); + of_node_put(np); + if (!scu_base) + return; + scu_enable(scu_base); + iounmap(scu_base); + } np = of_find_compatible_node(NULL, NULL, "marvell,berlin-cpu-ctrl"); cpu_ctrl = of_iomap(np, 0); of_node_put(np); if (!cpu_ctrl) - goto unmap_scu; + return; vectors_base = ioremap(CONFIG_VECTORS_BASE, SZ_32K); if (!vectors_base) - goto unmap_scu; + return; - scu_enable(scu_base); flush_cache_all(); /* @@ -87,8 +90,6 @@ static void __init berlin_smp_prepare_cpus(unsigned int max_cpus) writel(virt_to_phys(secondary_startup), vectors_base + SW_RESET_ADDR); iounmap(vectors_base); -unmap_scu: - iounmap(scu_base); } static struct smp_operations berlin_smp_ops __initdata = {