Re: [Qemu-devel] [PATCH] msi/msix: added API to set MSI message address and data

[Jan Kiszka]

On 2012-06-21 13:39, Alexey Kardashevskiy wrote:
> Added (msi|msix)_set_message() functions.
> 
> Currently msi_notify()/msix_notify() write to these vectors to
> signal the guest about an interrupt so the correct values have to
> written there by the guest or QEMU.
> 
> For example, POWER guest never initializes MSI/MSIX vectors, instead
> it uses RTAS hypercalls. So in order to support MSIX for virtio-pci on
> POWER we have to initialize MSI/MSIX message from QEMU.
> 
> Signed-off-by: Alexey Kardashevskiy <address@hidden>
> ---
>  hw/msi.c  |   13 +++++++++++++
>  hw/msi.h  |    1 +
>  hw/msix.c |    9 +++++++++
>  hw/msix.h |    2 ++
>  4 files changed, 25 insertions(+)
> 
> diff --git a/hw/msi.c b/hw/msi.c
> index 5233204..cc6102f 100644
> --- a/hw/msi.c
> +++ b/hw/msi.c
> @@ -105,6 +105,19 @@ static inline uint8_t msi_pending_off(const PCIDevice* 
> dev, bool msi64bit)
>      return dev->msi_cap + (msi64bit ? PCI_MSI_PENDING_64 : 
> PCI_MSI_PENDING_32);
>  }
>  
> +void msi_set_message(PCIDevice *dev, MSIMessage msg)
> +{
> +    uint16_t flags = pci_get_word(dev->config + msi_flags_off(dev));
> +    bool msi64bit = flags & PCI_MSI_FLAGS_64BIT;
> +
> +    if (msi64bit) {
> +        pci_set_quad(dev->config + msi_address_lo_off(dev), msg.address);
> +    } else {
> +        pci_set_long(dev->config + msi_address_lo_off(dev), msg.address);
> +    }
> +    pci_set_word(dev->config + msi_data_off(dev, msi64bit), msg.data);
> +}
> +
>  bool msi_enabled(const PCIDevice *dev)
>  {
>      return msi_present(dev) &&
> diff --git a/hw/msi.h b/hw/msi.h
> index 75747ab..6ec1f99 100644
> --- a/hw/msi.h
> +++ b/hw/msi.h
> @@ -31,6 +31,7 @@ struct MSIMessage {
>  
>  extern bool msi_supported;
>  
> +void msi_set_message(PCIDevice *dev, MSIMessage msg);
>  bool msi_enabled(const PCIDevice *dev);
>  int msi_init(struct PCIDevice *dev, uint8_t offset,
>               unsigned int nr_vectors, bool msi64bit, bool 
> msi_per_vector_mask);
> diff --git a/hw/msix.c b/hw/msix.c
> index ded3c55..5f7d6d3 100644
> --- a/hw/msix.c
> +++ b/hw/msix.c
> @@ -45,6 +45,15 @@ static MSIMessage msix_get_message(PCIDevice *dev, 
> unsigned vector)
>      return msg;
>  }
>  
> +void msix_set_message(PCIDevice *dev, int vector, struct MSIMessage msg)
> +{
> +    uint8_t *table_entry = dev->msix_table_page + vector * 
> PCI_MSIX_ENTRY_SIZE;
> +
> +    pci_set_quad(table_entry + PCI_MSIX_ENTRY_LOWER_ADDR, msg.address);
> +    pci_set_long(table_entry + PCI_MSIX_ENTRY_DATA, msg.data);
> +    table_entry[PCI_MSIX_ENTRY_VECTOR_CTRL] &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
> +}
> +
>  /* Add MSI-X capability to the config space for the device. */
>  /* Given a bar and its size, add MSI-X table on top of it
>   * and fill MSI-X capability in the config space.
> diff --git a/hw/msix.h b/hw/msix.h
> index 50aee82..26a437e 100644
> --- a/hw/msix.h
> +++ b/hw/msix.h
> @@ -4,6 +4,8 @@
>  #include "qemu-common.h"
>  #include "pci.h"
>  
> +void msix_set_message(PCIDevice *dev, int vector, MSIMessage msg);
> +
>  int msix_init(PCIDevice *pdev, unsigned short nentries,
>                MemoryRegion *bar,
>                unsigned bar_nr, unsigned bar_size);
> 

Interface looks good as fas as I can tell (can't asses the POWER need
for clearing the mask bit on msix_set_message).

> -- 
> 1.7.10
> 
> ps. double '-' and git version is an end-of-patch scissor as I read 
> somewhere, cannot recall where exactly 

Check man git-am.

Jan

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