On Wed, Jun 13, 2012 at 10:51:19PM -0600, Alex Williamson wrote:
> msi_init() takes over a BAR without really specifying or allowing
> specification of how it does so. Instead, let's split it into
> two interfaces, one fully specified, and one trivially easy. This
> implements the latter. msix_init_exclusive_bar() takes over
> allocating and filling a PCI BAR _exclusively_ for the use of MSIX.
> When used, the matching msi_uninit_exclusive_bar() should be used
> to tear it down.
>
> Signed-off-by: Alex Williamson <alex.william...@redhat.com>
> ---
>
> hw/msix.c | 43 +++++++++++++++++++++++++++++++++++++++++++
> hw/msix.h | 3 +++
> hw/pci.h | 2 ++
> 3 files changed, 48 insertions(+)
>
> diff --git a/hw/msix.c b/hw/msix.c
> index b64f109..a4cdfb0 100644
> --- a/hw/msix.c
> +++ b/hw/msix.c
> @@ -299,6 +299,41 @@ err_config:
> return ret;
> }
>
> +int msix_init_exclusive_bar(PCIDevice *dev, unsigned short nentries,
> + uint8_t bar_nr)
> +{
> + int ret;
> + char *name;
> +
> + /*
> + * Migration compatibility dictates that this remains a 4k
> + * BAR with the vector table in the lower half and PBA in
> + * the upper half.
> + */
> + if (nentries * PCI_MSIX_ENTRY_SIZE > 2048) {
> + return -EINVAL;
> + }
> +
> + if (asprintf(&name, "%s MSIX BAR", dev->name) == -1) {
> + return -ENOMEM;
> + }
> +
I think we should avoid spaces in names.
Also let's use lower case. And BAR is confusing IMO:
it's not a base address register, it's the region.
So I would prefer simply: "%s-msix".
> + memory_region_init(&dev->msix_exclusive_bar, name, 4096);
> +
> + free(name);
> +
> + ret = msix_init(dev, nentries, &dev->msix_exclusive_bar, bar_nr, 4096);
> + if (ret) {
> + memory_region_destroy(&dev->msix_exclusive_bar);
> + return ret;
> + }
> +
> + pci_register_bar(dev, bar_nr, PCI_BASE_ADDRESS_SPACE_MEMORY,
> + &dev->msix_exclusive_bar);
> +
> + return 0;
> +}
> +
> static void msix_free_irq_entries(PCIDevice *dev)
> {
> int vector;
> @@ -329,6 +364,14 @@ int msix_uninit(PCIDevice *dev, MemoryRegion *bar)
> return 0;
> }
>
> +void msix_uninit_exclusive_bar(PCIDevice *dev)
> +{
> + if (msix_present(dev)) {
> + msix_uninit(dev, &dev->msix_exclusive_bar);
> + memory_region_destroy(&dev->msix_exclusive_bar);
> + }
> +}
> +
> void msix_save(PCIDevice *dev, QEMUFile *f)
> {
> unsigned n = dev->msix_entries_nr;
> diff --git a/hw/msix.h b/hw/msix.h
> index e5a488d..bed6bfb 100644
> --- a/hw/msix.h
> +++ b/hw/msix.h
> @@ -7,11 +7,14 @@
> int msix_init(PCIDevice *pdev, unsigned short nentries,
> MemoryRegion *bar,
> unsigned bar_nr, unsigned bar_size);
> +int msix_init_exclusive_bar(PCIDevice *dev, unsigned short nentries,
> + uint8_t bar_nr);
>
> void msix_write_config(PCIDevice *pci_dev, uint32_t address,
> uint32_t val, int len);
>
> int msix_uninit(PCIDevice *d, MemoryRegion *bar);
> +void msix_uninit_exclusive_bar(PCIDevice *dev);
>
> unsigned int msix_nr_vectors_allocated(const PCIDevice *dev);
>
> diff --git a/hw/pci.h b/hw/pci.h
> index 4c96268..d517a54 100644
> --- a/hw/pci.h
> +++ b/hw/pci.h
> @@ -226,6 +226,8 @@ struct PCIDevice {
>
> /* Space to store MSIX table */
> uint8_t *msix_table_page;
> + /* MemoryRegion container for msix exclusive BAR setup */
> + MemoryRegion msix_exclusive_bar;
> /* MMIO index used to map MSIX table and pending bit entries. */
> MemoryRegion msix_mmio;
> /* Reference-count for entries actually in use by driver. */
