lkml.org 
[lkml]   [2015]   [Oct]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2 2/3] irqchip: irq-mips-gic: Provide function to map GIC user section
On 12/10/15 10:40, Markos Chandras wrote:
> From: Alex Smith <alex.smith@imgtec.com>
>
> The GIC provides a "user-mode visible" section containing a mirror of
> the counter registers which can be mapped into user memory. This will
> be used by the VDSO time function implementations, so provide a
> function to map it in.
>
> When the GIC is not enabled in Kconfig a dummy inline version of this
> function is provided, along with "#define gic_present 0", so that we
> don't have to litter the VDSO code with ifdefs.
>
> [markos.chandras@imgtec.com:
> - Move mapping code to arch/mips/kernel/vdso.c and use a resource
> type to get the GIC usermode information
> - Avoid renaming function arguments and use __gic_base_addr to hold
> the base GIC address prior to ioremap.]
>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Jason Cooper <jason@lakedaemon.net>
> Cc: Marc Zyngier <marc.zyngier@arm.com>
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Alex Smith <alex.smith@imgtec.com>
> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
> ---
> Changes since v1:
> - Move mapping code to arch/mips/kernel/vdso.c and use a resource
> type to get the GIC usermode information
> - Avoid renaming function arguments and use __gic_base_addr to hold
> the base GIC address prior to ioremap.
>
> http://www.linux-mips.org/archives/linux-mips/2015-09/msg00316.html
> ---
> drivers/irqchip/irq-mips-gic.c | 14 ++++++++++++++
> include/linux/irqchip/mips-gic.h | 17 +++++++++++++++++
> 2 files changed, 31 insertions(+)
>
> diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c
> index af2f16bb8a94..392beebb81ee 100644
> --- a/drivers/irqchip/irq-mips-gic.c
> +++ b/drivers/irqchip/irq-mips-gic.c
> @@ -29,6 +29,7 @@ struct gic_pcpu_mask {
> DECLARE_BITMAP(pcpu_mask, GIC_MAX_INTRS);
> };
>
> +static unsigned long __gic_base_addr;
> static void __iomem *gic_base;
> static struct gic_pcpu_mask pcpu_masks[NR_CPUS];
> static DEFINE_SPINLOCK(gic_lock);
> @@ -301,6 +302,17 @@ int gic_get_c0_fdc_int(void)
> GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_FDC));
> }
>
> +int gic_get_usm_range(struct resource *gic_usm_res)
> +{
> + if (!gic_present)
> + return -1;
> +
> + gic_usm_res->start = __gic_base_addr + USM_VISIBLE_SECTION_OFS;
> + gic_usm_res->end = gic_usm_res->start + (USM_VISIBLE_SECTION_SIZE - 1);
> +
> + return 0;
> +}
> +
> static void gic_handle_shared_int(bool chained)
> {
> unsigned int i, intr, virq, gic_reg_step = mips_cm_is64 ? 8 : 4;
> @@ -790,6 +802,8 @@ static void __init __gic_init(unsigned long gic_base_addr,
> {
> unsigned int gicconfig;
>
> + __gic_base_addr = gic_base_addr;
> +
> gic_base = ioremap_nocache(gic_base_addr, gic_addrspace_size);
>
> gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
> diff --git a/include/linux/irqchip/mips-gic.h b/include/linux/irqchip/mips-gic.h
> index 4e6861605050..71ab7c548550 100644
> --- a/include/linux/irqchip/mips-gic.h
> +++ b/include/linux/irqchip/mips-gic.h
> @@ -9,6 +9,7 @@
> #define __LINUX_IRQCHIP_MIPS_GIC_H
>
> #include <linux/clocksource.h>
> +#include <linux/ioport.h>
>
> #define GIC_MAX_INTRS 256
>
> @@ -245,6 +246,8 @@
> #define GIC_SHARED_TO_HWIRQ(x) (GIC_SHARED_HWIRQ_BASE + (x))
> #define GIC_HWIRQ_TO_SHARED(x) ((x) - GIC_SHARED_HWIRQ_BASE)
>
> +#ifdef CONFIG_MIPS_GIC
> +
> extern unsigned int gic_present;
>
> extern void gic_init(unsigned long gic_base_addr,
> @@ -264,4 +267,18 @@ extern unsigned int plat_ipi_resched_int_xlate(unsigned int);
> extern int gic_get_c0_compare_int(void);
> extern int gic_get_c0_perfcount_int(void);
> extern int gic_get_c0_fdc_int(void);
> +extern int gic_get_usm_range(struct resource *gic_usm_res);
> +
> +#else /* CONFIG_MIPS_GIC */
> +
> +#define gic_present 0
> +
> +static int gic_get_usm_range(struct resource *gic_usm_res)
> +{
> + /* Shouldn't be called. */
> + return -1
> +}
> +
> +#endif /* CONFIG_MIPS_GIC */
> +
> #endif /* __LINUX_IRQCHIP_MIPS_GIC_H */
>

This looks much better than the previous version (though I cannot find
the two other patches on LKML just yet).

FWIW:

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

M.
--
Jazz is not dead. It just smells funny...


\
 
 \ /
  Last update: 2015-10-12 12:21    [W:0.158 / U:0.308 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site