Replace BAR flags with unified layout parameter
#41
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This change updates pci_set_bar() to accept a single `layout` bitmask instead of separate boolean flags, simplifying BAR configuration. The new `layout` argument encodes I/O vs. memory space, 32-/64-bit decoding, and prefetchable settings via standard PCI_BASE_ADDRESS_* macros. Existing callers can now pass any combination of: - PCI_BASE_ADDRESS_SPACE_IO or PCI_BASE_ADDRESS_SPACE_MEMORY - PCI_BASE_ADDRESS_MEM_TYPE_32 or PCI_BASE_ADDRESS_MEM_TYPE_64 - PCI_BASE_ADDRESS_MEM_PREFETCH The function writes the full layout to the BAR, derives `bar_is_io_space` from bit[0], and initializes the region with the provided callback. Docstrings updated with Doxygen examples illustrating MMIO and port I/O. BREAKING CHANGE: pci_set_bar() signature changed; call sites must be updated to pass the new `layout` parameter rather than separate flags.
jserv
reviewed
Jul 4, 2025
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| /** | ||
| * @brief Configure and initialize a PCI Base Address Register (BAR). | ||
| * | ||
| * This writes the caller-provided layout bitmask into the BAR register | ||
| * in the PCI configuration header, records the region size and I/O type, | ||
| * and sets up the address space (MMIO or port I/O) with the specified | ||
| * callback. | ||
| * | ||
| * @param dev Pointer to the pci_dev representing the device. | ||
| * @param bar BAR index to program (0–5 in a standard PCI header). | ||
| * @param bar_size Size of the BAR region in bytes (must be a power of two). | ||
| * @param layout Bitmask of PCI_BASE_ADDRESS_* flags defined in | ||
| * `/usr/include/linux/pci_regs.h`: | ||
| * - Bit 0: I/O space (1) vs. memory space (0) | ||
| * (`PCI_BASE_ADDRESS_SPACE_IO` or | ||
| * `PCI_BASE_ADDRESS_SPACE_MEMORY`) | ||
| * - Bits [2:1]: Memory decoding type | ||
| * (`PCI_BASE_ADDRESS_MEM_TYPE_32` or | ||
| * `PCI_BASE_ADDRESS_MEM_TYPE_64`) | ||
| * - Bit 3: Prefetchable flag for memory | ||
| * (`PCI_BASE_ADDRESS_MEM_PREFETCH`) | ||
| * @param do_io Callback (dev_io_fn) invoked on accesses within | ||
| * the BAR region. | ||
| * | ||
| * @note bar_size must be a power of two for correct decoding by the | ||
| * PCI framework. | ||
| * @note For 64-bit memory BARs, callers must reserve the next BAR index | ||
| * (n+1) for the high 32 bits if required by the platform. | ||
| */ |
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jserv
reviewed
Jul 4, 2025
| @@ -268,7 +268,9 @@ void virtio_pci_init(struct virtio_pci_dev *dev, | |||
| PCI_HDR_WRITE(dev->pci_dev.hdr, PCI_HEADER_TYPE, PCI_HEADER_TYPE_NORMAL, 8); | |||
| PCI_HDR_WRITE(dev->pci_dev.hdr, PCI_INTERRUPT_PIN, 1, 8); | |||
| pci_set_status(&dev->pci_dev, PCI_STATUS_CAP_LIST | PCI_STATUS_INTERRUPT); | |||
| pci_set_bar(&dev->pci_dev, 0, 0x100, PCI_BASE_ADDRESS_SPACE_MEMORY, | |||
| pci_set_bar(&dev->pci_dev, 0, 0x100, | |||
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This change updates pci_set_bar() to accept a single
layoutbitmask instead of separate boolean flags, simplifying BAR configuration. The newlayoutargument encodes I/O vs. memory space, 32-/64-bit decoding, and prefetchable settings via standard PCI_BASE_ADDRESS_* macros. Existing callers can now pass any combination of:bar_is_io_spacefrom bit[0], and initializes the region with the provided callback. Docstrings updated with Doxygen examples illustrating MMIO and port I/O.BREAKING CHANGE: pci_set_bar() signature changed; call sites must be updated to pass the new
layoutparameter rather than separate flags.