Subject: Re: [RFC PATCH 16/19] powerpc: wii: hollywood interrupt controller support

From: Albert Herranz <[email-masked]>
Date: Mon, 23 Nov 2009 21:18:51 +0100

Grant Likely wrote:
> On Sun, Nov 22, 2009 at 3:01 PM, Albert Herranz <[email-masked]> wrote:
>> Add support for the dual interrupt controller included in the "Hollywood"
>> chipset of the Nintendo Wii video game console.
>> This interrupt controller serves both the Broadway processor (as a cascade)
>> and the Starlet processor, and is used to manage interrupts for the
>> non-classic hardware.
>>
>> Signed-off-by: Albert Herranz <[email-masked]>
> 
> On brief glance...
> 
> Acked-by: Grant Likely <[email-masked]>
> 

Uhmmm... I think I should use .name instead of .typename in struct irq_chip, no?

>> ---
>>  arch/powerpc/platforms/embedded6xx/Kconfig    |    5 +
>>  arch/powerpc/platforms/embedded6xx/Makefile   |    1 +
>>  arch/powerpc/platforms/embedded6xx/hlwd-pic.c |  238 +++++++++++++++++++++++++
>>  arch/powerpc/platforms/embedded6xx/hlwd-pic.h |   22 +++
>>  4 files changed, 266 insertions(+), 0 deletions(-)
>>  create mode 100644 arch/powerpc/platforms/embedded6xx/hlwd-pic.c
>>  create mode 100644 arch/powerpc/platforms/embedded6xx/hlwd-pic.h
>>
>> diff --git a/arch/powerpc/platforms/embedded6xx/Kconfig b/arch/powerpc/platforms/embedded6xx/Kconfig
>> index efb2ea1..490f89e 100644
>> --- a/arch/powerpc/platforms/embedded6xx/Kconfig
>> +++ b/arch/powerpc/platforms/embedded6xx/Kconfig
>> @@ -122,3 +122,8 @@ config GAMECUBE
>>          Select GAMECUBE if configuring for the Nintendo GameCube.
>>          More information at: <http://gc-linux.sourceforge.net/>
>>
>> +config HLWD_PIC
>> +       bool
>> +       depends on STARLET_MINI
>> +       default y
>> +
>> diff --git a/arch/powerpc/platforms/embedded6xx/Makefile b/arch/powerpc/platforms/embedded6xx/Makefile
>> index b0324ed..c1dcc54 100644
>> --- a/arch/powerpc/platforms/embedded6xx/Makefile
>> +++ b/arch/powerpc/platforms/embedded6xx/Makefile
>> @@ -10,3 +10,4 @@ obj-$(CONFIG_PPC_C2K)         += c2k.o
>>  obj-$(CONFIG_USBGECKO_UDBG)    += usbgecko_udbg.o
>>  obj-$(CONFIG_FLIPPER_PIC)      += flipper-pic.o
>>  obj-$(CONFIG_GAMECUBE)         += gamecube.o gamecube_dev.o
>> +obj-$(CONFIG_HLWD_PIC)         += hlwd-pic.o
>> diff --git a/arch/powerpc/platforms/embedded6xx/hlwd-pic.c b/arch/powerpc/platforms/embedded6xx/hlwd-pic.c
>> new file mode 100644
>> index 0000000..b024800
>> --- /dev/null
>> +++ b/arch/powerpc/platforms/embedded6xx/hlwd-pic.c
>> @@ -0,0 +1,238 @@
>> +/*
>> + * arch/powerpc/platforms/embedded6xx/hlwd-pic.c
>> + *
>> + * Nintendo Wii "Hollywood" interrupt controller support.
>> + * Copyright (C) 2009 The GameCube Linux Team
>> + * Copyright (C) 2009 Albert Herranz
>> + *
>> + * This program is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU General Public License
>> + * as published by the Free Software Foundation; either version 2
>> + * of the License, or (at your option) any later version.
>> + *
>> + */
>> +#define DRV_MODULE_NAME "hlwd-pic"
>> +#define pr_fmt(fmt) DRV_MODULE_NAME ": " fmt
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/init.h>
>> +#include <linux/irq.h>
>> +#include <linux/of.h>
>> +#include <asm/io.h>
>> +
>> +#include "hlwd-pic.h"
>> +
>> +#define HLWD_NR_IRQS   32
>> +
>> +/*
>> + * Each interrupt has a corresponding bit in both
>> + * the Interrupt Cause (ICR) and Interrupt Mask (IMR) registers.
>> + *
>> + * Enabling/disabling an interrupt line involves asserting/clearing
>> + * the corresponding bit in IMR. ACK'ing a request simply involves
>> + * asserting the corresponding bit in ICR.
>> + */
>> +#define HW_BROADWAY_ICR                0x00
>> +#define HW_BROADWAY_IMR                0x04
>> +
>> +
>> +/*
>> + * IRQ chip hooks.
>> + *
>> + */
>> +
>> +static void hlwd_pic_mask_and_ack(unsigned int virq)
>> +{
>> +       int irq = virq_to_hw(virq);
>> +       void __iomem *io_base = get_irq_chip_data(virq);
>> +
>> +       clear_bit(irq, io_base + HW_BROADWAY_IMR);
>> +       set_bit(irq, io_base + HW_BROADWAY_ICR);
>> +}
>> +
>> +static void hlwd_pic_ack(unsigned int virq)
>> +{
>> +       int irq = virq_to_hw(virq);
>> +       void __iomem *io_base = get_irq_chip_data(virq);
>> +
>> +       set_bit(irq, io_base + HW_BROADWAY_ICR);
>> +}
>> +
>> +static void hlwd_pic_mask(unsigned int virq)
>> +{
>> +       int irq = virq_to_hw(virq);
>> +       void __iomem *io_base = get_irq_chip_data(virq);
>> +
>> +       clear_bit(irq, io_base + HW_BROADWAY_IMR);
>> +}
>> +
>> +static void hlwd_pic_unmask(unsigned int virq)
>> +{
>> +       int irq = virq_to_hw(virq);
>> +       void __iomem *io_base = get_irq_chip_data(virq);
>> +
>> +       set_bit(irq, io_base + HW_BROADWAY_IMR);
>> +}
>> +
>> +
>> +static struct irq_chip hlwd_pic = {
>> +       .typename       = "hlwd-pic",
>> +       .ack            = hlwd_pic_ack,
>> +       .mask_ack       = hlwd_pic_mask_and_ack,
>> +       .mask           = hlwd_pic_mask,
>> +       .unmask         = hlwd_pic_unmask,
>> +};
>> +
>> +/*
>> + * IRQ host hooks.
>> + *
>> + */
>> +
>> +static struct irq_host *hlwd_irq_host;
>> +
>> +static int hlwd_pic_map(struct irq_host *h, unsigned int virq,
>> +                          irq_hw_number_t hwirq)
>> +{
>> +       set_irq_chip_data(virq, h->host_data);
>> +       get_irq_desc(virq)->status |= IRQ_LEVEL;
>> +       set_irq_chip_and_handler(virq, &hlwd_pic, handle_level_irq);
>> +       return 0;
>> +}
>> +
>> +static void hlwd_pic_unmap(struct irq_host *h, unsigned int irq)
>> +{
>> +       set_irq_chip_data(irq, NULL);
>> +       set_irq_chip(irq, NULL);
>> +}
>> +
>> +static struct irq_host_ops hlwd_irq_host_ops = {
>> +       .map = hlwd_pic_map,
>> +       .unmap = hlwd_pic_unmap,
>> +};
>> +
>> +static unsigned int __hlwd_pic_get_irq(struct irq_host *h)
>> +{
>> +       void __iomem *io_base = h->host_data;
>> +       int irq;
>> +       u32 irq_status;
>> +
>> +       irq_status = in_be32(io_base + HW_BROADWAY_ICR) &
>> +                    in_be32(io_base + HW_BROADWAY_IMR);
>> +       if (irq_status == 0)
>> +               return NO_IRQ_IGNORE;   /* no more IRQs pending */
>> +
>> +       __asm__ __volatile__("cntlzw %0,%1" : "=r"(irq) : "r"(irq_status));
>> +       return irq_linear_revmap(h, 31 - irq);
>> +}
>> +
>> +static void hlwd_pic_irq_cascade(unsigned int cascade_virq,
>> +                                     struct irq_desc *desc)
>> +{
>> +       struct irq_host *irq_host = get_irq_data(cascade_virq);
>> +       unsigned int virq;
>> +
>> +       spin_lock(&desc->lock);
>> +       desc->chip->mask(cascade_virq); /* IRQ_LEVEL */
>> +       spin_unlock(&desc->lock);
>> +
>> +       virq = __hlwd_pic_get_irq(irq_host);
>> +       if (virq != NO_IRQ_IGNORE)
>> +               generic_handle_irq(virq);
>> +       else
>> +               pr_err("spurious interrupt!\n");
>> +
>> +       spin_lock(&desc->lock);
>> +       desc->chip->ack(cascade_virq); /* IRQ_LEVEL */
>> +       if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
>> +               desc->chip->unmask(cascade_virq);
>> +       spin_unlock(&desc->lock);
>> +}
>> +
>> +/*
>> + * Platform hooks.
>> + *
>> + */
>> +
>> +static void __hlwd_quiesce(void __iomem *io_base)
>> +{
>> +       /* mask and ack all IRQs */
>> +       out_be32(io_base + HW_BROADWAY_IMR, 0);
>> +       out_be32(io_base + HW_BROADWAY_ICR, ~0);
>> +}
>> +
>> +struct irq_host *hlwd_pic_init(struct device_node *np)
>> +{
>> +       struct irq_host *irq_host;
>> +       struct resource res;
>> +       void __iomem *io_base;
>> +       int retval;
>> +
>> +       retval = of_address_to_resource(np, 0, &res);
>> +       if (retval) {
>> +               pr_err("no io memory range found\n");
>> +               return NULL;
>> +       }
>> +       io_base = ioremap(res.start, resource_size(&res));
>> +       if (!io_base) {
>> +               pr_err("ioremap failed\n");
>> +               return NULL;
>> +       }
>> +
>> +       pr_info("controller at 0x%08x mapped to 0x%p\n", res.start, io_base);
>> +
>> +       __hlwd_quiesce(io_base);
>> +
>> +       irq_host = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, HLWD_NR_IRQS,
>> +                                 &hlwd_irq_host_ops, NO_IRQ_IGNORE);
>> +       if (!irq_host) {
>> +               pr_err("failed to allocate irq_host\n");
>> +               return NULL;
>> +       }
>> +       irq_host->host_data = io_base;
>> +
>> +       return irq_host;
>> +}
>> +
>> +unsigned int hlwd_pic_get_irq(void)
>> +{
>> +       return __hlwd_pic_get_irq(hlwd_irq_host);
>> +}
>> +
>> +/*
>> + * Probe function.
>> + *
>> + */
>> +
>> +void hlwd_pic_probe(void)
>> +{
>> +       struct irq_host *host;
>> +       struct device_node *np;
>> +       const u32 *interrupts;
>> +       int cascade_virq;
>> +
>> +       for_each_compatible_node(np, NULL, "nintendo,hollywood-pic") {
>> +               interrupts = of_get_property(np, "interrupts", NULL);
>> +               if (interrupts) {
>> +                       host = hlwd_pic_init(np);
>> +                       BUG_ON(!host);
>> +                       cascade_virq = irq_of_parse_and_map(np, 0);
>> +                       set_irq_data(cascade_virq, host);
>> +                       set_irq_chained_handler(cascade_virq,
>> +                                               hlwd_pic_irq_cascade);
>> +               }
>> +       }
>> +}
>> +
>> +/**
>> + * hlwd_quiesce() - quiesce hollywood irq controller
>> + *
>> + * Mask and ack all interrupt sources.
>> + *
>> + */
>> +void hlwd_quiesce(void)
>> +{
>> +       void __iomem *io_base = hlwd_irq_host->host_data;
>> +
>> +       __hlwd_quiesce(io_base);
>> +}
>> +
>> diff --git a/arch/powerpc/platforms/embedded6xx/hlwd-pic.h b/arch/powerpc/platforms/embedded6xx/hlwd-pic.h
>> new file mode 100644
>> index 0000000..d2e5a09
>> --- /dev/null
>> +++ b/arch/powerpc/platforms/embedded6xx/hlwd-pic.h
>> @@ -0,0 +1,22 @@
>> +/*
>> + * arch/powerpc/platforms/embedded6xx/hlwd-pic.h
>> + *
>> + * Nintendo Wii "Hollywood" interrupt controller support.
>> + * Copyright (C) 2009 The GameCube Linux Team
>> + * Copyright (C) 2009 Albert Herranz
>> + *
>> + * This program is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU General Public License
>> + * as published by the Free Software Foundation; either version 2
>> + * of the License, or (at your option) any later version.
>> + *
>> + */
>> +
>> +#ifndef __HLWD_PIC_H
>> +#define __HLWD_PIC_H
>> +
>> +extern unsigned int hlwd_pic_get_irq(void);
>> +extern void hlwd_pic_probe(void);
>> +extern void hlwd_quiesce(void);
>> +
>> +#endif
>> --
>> 1.6.3.3
>>
>> _______________________________________________
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>> https://lists.ozlabs.org/listinfo/linuxppc-dev
>>
> 
> 
> 

Cheers,
Albert