Re: [PATCH v1 01/23] pc/xen: Xen Q35 support: provide IRQ handling for PCI devices

["Daniel P. Berrangé" <berrange@redhat.com>]

On Tue, Jun 20, 2023 at 01:24:34PM -0400, Joel Upham wrote:
> 
> Signed-off-by: Alexey Gerasimenko <x1917x@xxxxxxxxx>

This isn't a valid email address for Alexey - I presume you grabbed
these patches from the xen-devel mail archives, which have mangled
the addresses for anti-spam reasons.

Fortunately there are alternative archives which don't mangle the
patches:

  https://lore.kernel.org/xen-devel/6067bc3c91c9ee629a35723dfb474ef168ff4ebf.1520867955.git.x1917x@gmail.com/

  Signed-off-by: Alexey Gerasimenko <x1917x@gmail.com>

This affects all patches in the series, but I won't repeat my
comment on each one.

> Signed-off-by: Joel Upham <jupham125@gmail.com>
> ---
>  hw/i386/pc_piix.c             |  3 +-
>  hw/i386/xen/xen-hvm.c         |  7 +++--
>  hw/isa/lpc_ich9.c             | 53 ++++++++++++++++++++++++++++++++---
>  hw/isa/piix3.c                |  2 +-
>  include/hw/southbridge/ich9.h |  1 +
>  include/hw/xen/xen.h          |  4 +--
>  stubs/xen-hw-stub.c           |  4 +--
>  7 files changed, 61 insertions(+), 13 deletions(-)
> 
> diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
> index d5b0dcd1fe..8c1b20f3bc 100644
> --- a/hw/i386/pc_piix.c
> +++ b/hw/i386/pc_piix.c
> @@ -62,6 +62,7 @@
>  #endif
>  #include "hw/xen/xen-x86.h"
>  #include "hw/xen/xen.h"
> +#include "sysemu/xen.h"
>  #include "migration/global_state.h"
>  #include "migration/misc.h"
>  #include "sysemu/numa.h"
> @@ -233,7 +234,7 @@ static void pc_init1(MachineState *machine,
>                                x86ms->above_4g_mem_size,
>                                pci_memory, ram_memory);
>          pci_bus_map_irqs(pci_bus,
> -                         xen_enabled() ? xen_pci_slot_get_pirq
> +                         xen_enabled() ? xen_cmn_pci_slot_get_pirq
>                                         : pc_pci_slot_get_pirq);
>          pcms->bus = pci_bus;
>  
> diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c
> index 56641a550e..540ac46639 100644
> --- a/hw/i386/xen/xen-hvm.c
> +++ b/hw/i386/xen/xen-hvm.c
> @@ -15,6 +15,7 @@
>  #include "hw/pci/pci.h"
>  #include "hw/pci/pci_host.h"
>  #include "hw/i386/pc.h"
> +#include "hw/southbridge/ich9.h"
>  #include "hw/irq.h"
>  #include "hw/hw.h"
>  #include "hw/i386/apic-msidef.h"
> @@ -136,14 +137,14 @@ typedef struct XenIOState {
>      Notifier wakeup;
>  } XenIOState;
>  
> -/* Xen specific function for piix pci */
> +/* Xen-specific functions for pci dev IRQ handling */
>  
> -int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
> +int xen_cmn_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
>  {
>      return irq_num + (PCI_SLOT(pci_dev->devfn) << 2);
>  }
>  
> -void xen_piix3_set_irq(void *opaque, int irq_num, int level)
> +void xen_cmn_set_irq(void *opaque, int irq_num, int level)
>  {
>      xen_set_pci_intx_level(xen_domid, 0, 0, irq_num >> 2,
>                             irq_num & 3, level);
> diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
> index 9c47a2f6c7..733a99d443 100644
> --- a/hw/isa/lpc_ich9.c
> +++ b/hw/isa/lpc_ich9.c
> @@ -51,6 +51,9 @@
>  #include "hw/core/cpu.h"
>  #include "hw/nvram/fw_cfg.h"
>  #include "qemu/cutils.h"
> +#include "hw/xen/xen.h"
> +#include "sysemu/xen.h"
> +#include "hw/southbridge/piix.h"
>  #include "hw/acpi/acpi_aml_interface.h"
>  #include "trace.h"
>  
> @@ -535,11 +538,49 @@ static int ich9_lpc_post_load(void *opaque, int version_id)
>      return 0;
>  }
>  
> +static void ich9_lpc_config_write_xen(PCIDevice *d,
> +                                  uint32_t addr, uint32_t val, int len)
> +{
> +    static bool pirqe_f_warned = false;
> +    if (ranges_overlap(addr, len, ICH9_LPC_PIRQA_ROUT, 4)) {
> +        /* handle PIRQA..PIRQD routing */
> +        /* Scan for updates to PCI link routes (0x60-0x63). */
> +        int i;
> +        for (i = 0; i < len; i++) {
> +            uint8_t v = (val >> (8 * i)) & 0xff;
> +            if (v & 0x80) {
> +                v = 0;
> +            }
> +            v &= 0xf;
> +            if (((addr + i) >= PIIX_PIRQCA) && ((addr + i) <= PIIX_PIRQCD)) {
> +                xen_set_pci_link_route(addr + i - PIIX_PIRQCA, v);
> +            }
> +        }
> +    } else if (ranges_overlap(addr, len, ICH9_LPC_PIRQE_ROUT, 4)) {
> +        while (len--) {
> +            if (range_covers_byte(ICH9_LPC_PIRQE_ROUT, 4, addr) &&
> +                (val & 0x80) == 0) {
> +                /* print warning only once */
> +                if (!pirqe_f_warned) {
> +                    pirqe_f_warned = true;
> +                    fprintf(stderr, "WARNING: guest domain attempted to use PIRQ%c "
> +                            "routing which is not supported for Xen/Q35 currently\n",
> +                            (char)(addr - ICH9_LPC_PIRQE_ROUT + 'E'));
> +                    break;
> +                }
> +            }
> +            addr++, val >>= 8;
> +        }
> +    }
> +}
> +
>  static void ich9_lpc_config_write(PCIDevice *d,
>                                    uint32_t addr, uint32_t val, int len)
>  {
>      ICH9LPCState *lpc = ICH9_LPC_DEVICE(d);
>      uint32_t rcba_old = pci_get_long(d->config + ICH9_LPC_RCBA);
> +    if (xen_enabled())
> +        ich9_lpc_config_write_xen(d, addr, val, len);
>  
>      pci_default_write_config(d, addr, val, len);
>      if (ranges_overlap(addr, len, ICH9_LPC_PMBASE, 4) ||
> @@ -731,10 +772,14 @@ static void ich9_lpc_realize(PCIDevice *d, Error **errp)
>          return;
>      }
>  
> -    pci_bus_irqs(pci_bus, ich9_lpc_set_irq, d, ICH9_LPC_NB_PIRQS);
> -    pci_bus_map_irqs(pci_bus, ich9_lpc_map_irq);
> -    pci_bus_set_route_irq_fn(pci_bus, ich9_route_intx_pin_to_irq);
> -
> +    if (xen_enabled()) {
> +        pci_bus_irqs(pci_bus, xen_cmn_set_irq, d, ICH9_XEN_NUM_IRQ_SOURCES);
> +        pci_bus_map_irqs(pci_bus, xen_cmn_pci_slot_get_pirq);
> +    } else {
> +        pci_bus_irqs(pci_bus, ich9_lpc_set_irq, d, ICH9_LPC_NB_PIRQS);
> +        pci_bus_map_irqs(pci_bus, ich9_lpc_map_irq);
> +        pci_bus_set_route_irq_fn(pci_bus, ich9_route_intx_pin_to_irq);
> +    }
>      ich9_lpc_pm_init(lpc);
>  }
>  
> diff --git a/hw/isa/piix3.c b/hw/isa/piix3.c
> index f9103ea45a..3d0545eb0e 100644
> --- a/hw/isa/piix3.c
> +++ b/hw/isa/piix3.c
> @@ -420,7 +420,7 @@ static void piix3_xen_realize(PCIDevice *dev, Error **errp)
>       * connected to the IOAPIC directly.
>       * These additional routes can be discovered through ACPI.
>       */
> -    pci_bus_irqs(pci_bus, xen_piix3_set_irq, piix3, XEN_PIIX_NUM_PIRQS);
> +    pci_bus_irqs(pci_bus, xen_cmn_set_irq, piix3, XEN_PIIX_NUM_PIRQS);
>  }
>  
>  static void piix3_xen_class_init(ObjectClass *klass, void *data)
> diff --git a/include/hw/southbridge/ich9.h b/include/hw/southbridge/ich9.h
> index fd01649d04..07b84d5227 100644
> --- a/include/hw/southbridge/ich9.h
> +++ b/include/hw/southbridge/ich9.h
> @@ -130,6 +130,7 @@ struct ICH9LPCState {
>  
>  #define ICH9_A2_LPC_REVISION                    0x2
>  #define ICH9_LPC_NB_PIRQS                       8       /* PCI A-H */
> +#define ICH9_XEN_NUM_IRQ_SOURCES                128
>  
>  #define ICH9_LPC_PMBASE                         0x40
>  #define ICH9_LPC_PMBASE_BASE_ADDRESS_MASK       ICH9_MASK(32, 15, 7)
> diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
> index 2bd8ec742d..a2c3d98eaa 100644
> --- a/include/hw/xen/xen.h
> +++ b/include/hw/xen/xen.h
> @@ -37,9 +37,9 @@ extern uint32_t xen_domid;
>  extern enum xen_mode xen_mode;
>  extern bool xen_domid_restrict;
>  
> -int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num);
> +int xen_cmn_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num);
>  int xen_set_pci_link_route(uint8_t link, uint8_t irq);
> -void xen_piix3_set_irq(void *opaque, int irq_num, int level);
> +void xen_cmn_set_irq(void *opaque, int irq_num, int level);
>  void xen_hvm_inject_msi(uint64_t addr, uint32_t data);
>  int xen_is_pirq_msi(uint32_t msi_data);
>  
> diff --git a/stubs/xen-hw-stub.c b/stubs/xen-hw-stub.c
> index 34a22f2ad7..f06fbf48c8 100644
> --- a/stubs/xen-hw-stub.c
> +++ b/stubs/xen-hw-stub.c
> @@ -10,12 +10,12 @@
>  #include "hw/xen/xen.h"
>  #include "hw/xen/xen-x86.h"
>  
> -int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
> +int xen_cmn_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
>  {
>      return -1;
>  }
>  
> -void xen_piix3_set_irq(void *opaque, int irq_num, int level)
> +void xen_cmn_set_irq(void *opaque, int irq_num, int level)
>  {
>  }
>  
> -- 
> 2.34.1
> 
> 

With regards,
Daniel
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