Re: [PATCH 3/3] sam460ex: Clean up irq mapping

[Guenter Roeck <linux@roeck-us.net>]

On 12/25/20 3:07 PM, BALATON Zoltan wrote:
> Avoid mapping multiple interrupts to the same irq. Instead map them to
> the 4 PCI interrupts and use an or-gate in the board to connect them
> to the interrupt controller. This does not fix any known problem but
> does not seem to cause a new problem either and may be cleaner at least.
> 
> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>

Tested-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  hw/ppc/Kconfig       |  1 +
>  hw/ppc/ppc440_pcix.c | 28 ++++++++++++++--------------
>  hw/ppc/sam460ex.c    | 16 +++++++++++++---
>  3 files changed, 28 insertions(+), 17 deletions(-)
> 
> diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
> index 5893f80909..fabdb1a96f 100644
> --- a/hw/ppc/Kconfig
> +++ b/hw/ppc/Kconfig
> @@ -58,6 +58,7 @@ config SAM460EX
>      select PFLASH_CFI01
>      select IDE_SII3112
>      select M41T80
> +    select OR_IRQ
>      select PPC440
>      select SM501
>      select SMBUS_EEPROM
> diff --git a/hw/ppc/ppc440_pcix.c b/hw/ppc/ppc440_pcix.c
> index ee952314c8..504decbbc2 100644
> --- a/hw/ppc/ppc440_pcix.c
> +++ b/hw/ppc/ppc440_pcix.c
> @@ -57,8 +57,8 @@ struct PPC440PCIXState {
>      PCIDevice *dev;
>      struct PLBOutMap pom[PPC440_PCIX_NR_POMS];
>      struct PLBInMap pim[PPC440_PCIX_NR_PIMS];
> +    qemu_irq irq[PCI_NUM_PINS];
>      uint32_t sts;
> -    qemu_irq irq;
>      AddressSpace bm_as;
>      MemoryRegion bm;
>  
> @@ -415,24 +415,20 @@ static void ppc440_pcix_reset(DeviceState *dev)
>      s->sts = 0;
>  }
>  
> -/* All pins from each slot are tied to a single board IRQ.
> - * This may need further refactoring for other boards. */
>  static int ppc440_pcix_map_irq(PCIDevice *pci_dev, int irq_num)
>  {
> -    trace_ppc440_pcix_map_irq(pci_dev->devfn, irq_num, 0);
> -    return 0;
> +    int n = (irq_num + PCI_SLOT(pci_dev->devfn)) % PCI_NUM_PINS;
> +
> +    trace_ppc440_pcix_map_irq(pci_dev->devfn, irq_num, n);
> +    return n;
>  }
>  
>  static void ppc440_pcix_set_irq(void *opaque, int irq_num, int level)
>  {
> -    qemu_irq *pci_irq = opaque;
> +    qemu_irq *pci_irqs = opaque;
>  
>      trace_ppc440_pcix_set_irq(irq_num);
> -    if (irq_num < 0) {
> -        error_report("%s: PCI irq %d", __func__, irq_num);
> -        return;
> -    }
> -    qemu_set_irq(*pci_irq, level);
> +    qemu_set_irq(pci_irqs[irq_num], level);
>  }
>  
>  static AddressSpace *ppc440_pcix_set_iommu(PCIBus *b, void *opaque, int devfn)
> @@ -472,15 +468,19 @@ static void ppc440_pcix_realize(DeviceState *dev, Error **errp)
>      SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
>      PPC440PCIXState *s;
>      PCIHostState *h;
> +    int i;
>  
>      h = PCI_HOST_BRIDGE(dev);
>      s = PPC440_PCIX_HOST_BRIDGE(dev);
>  
> -    sysbus_init_irq(sbd, &s->irq);
> +    for (i = 0; i < ARRAY_SIZE(s->irq); i++) {
> +        sysbus_init_irq(sbd, &s->irq[i]);
> +    }
>      memory_region_init(&s->busmem, OBJECT(dev), "pci bus memory", UINT64_MAX);
>      h->bus = pci_register_root_bus(dev, NULL, ppc440_pcix_set_irq,
> -                         ppc440_pcix_map_irq, &s->irq, &s->busmem,
> -                         get_system_io(), PCI_DEVFN(0, 0), 1, TYPE_PCI_BUS);
> +                         ppc440_pcix_map_irq, s->irq, &s->busmem,
> +                         get_system_io(), PCI_DEVFN(0, 0), ARRAY_SIZE(s->irq),
> +                         TYPE_PCI_BUS);
>  
>      s->dev = pci_create_simple(h->bus, PCI_DEVFN(0, 0), "ppc4xx-host-bridge");
>  
> diff --git a/hw/ppc/sam460ex.c b/hw/ppc/sam460ex.c
> index 14e6583eb0..59b19fbca1 100644
> --- a/hw/ppc/sam460ex.c
> +++ b/hw/ppc/sam460ex.c
> @@ -33,6 +33,7 @@
>  #include "sysemu/qtest.h"
>  #include "sysemu/reset.h"
>  #include "hw/sysbus.h"
> +#include "hw/or-irq.h"
>  #include "hw/char/serial.h"
>  #include "hw/i2c/ppc4xx_i2c.h"
>  #include "hw/i2c/smbus_eeprom.h"
> @@ -292,7 +293,7 @@ static void sam460ex_init(MachineState *machine)
>      SysBusDevice *sbdev;
>      struct boot_info *boot_info;
>      uint8_t *spd_data;
> -    int success;
> +    int i, success;
>  
>      cpu = POWERPC_CPU(cpu_create(machine->cpu_type));
>      env = &cpu->env;
> @@ -382,13 +383,22 @@ static void sam460ex_init(MachineState *machine)
>  
>      /* PCI bus */
>      ppc460ex_pcie_init(env);
> -    /* All PCI irqs are connected to the same UIC pin (cf. UBoot source) */
> -    dev = sysbus_create_simple("ppc440-pcix-host", 0xc0ec00000, uic[1][0]);
> +    dev = sysbus_create_simple("ppc440-pcix-host", 0xc0ec00000, NULL);
>      pci_bus = (PCIBus *)qdev_get_child_bus(dev, "pci.0");
>      if (!pci_bus) {
>          error_report("couldn't create PCI controller!");
>          exit(1);
>      }
> +    /* All PCI irqs are connected to the same UIC pin (cf. UBoot source) */
> +    sbdev = SYS_BUS_DEVICE(dev);
> +    dev = qdev_new(TYPE_OR_IRQ);
> +    object_property_set_int(OBJECT(dev), "num-lines", PCI_NUM_PINS,
> +                            &error_fatal);
> +    qdev_realize_and_unref(dev, NULL, &error_fatal);
> +    for (i = 0; i < PCI_NUM_PINS; i++) {
> +        sysbus_connect_irq(sbdev, i, qdev_get_gpio_in(dev, i));
> +    }
> +    qdev_connect_gpio_out(dev, 0, uic[1][0]);
>      memory_region_init_alias(isa, NULL, "isa_mmio", get_system_io(),
>                               0, 0x10000);
>      memory_region_add_subregion(get_system_memory(), 0xc08000000, isa);
>