core: Introduce generic PCI config space access functions

If available, these functions use MMIO-based access. Otherwise, they
call the arch-specific access functions.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

diff --git a/hypervisor/include/jailhouse/pci.h b/hypervisor/include/jailhouse/pci.h
index fdb01d4338d73a105cc4fb71b6d18bc93f2b148c..696a93c8192ee4d6117807a8bde428e0e6895212 100644 (file)
--- a/hypervisor/include/jailhouse/pci.h
+++ b/hypervisor/include/jailhouse/pci.h
@@ -24,6 +24,9 @@ enum pci_access { PCI_ACCESS_REJECT, PCI_ACCESS_PERFORM, PCI_ACCESS_EMULATE };
 
 int pci_init(void);
 
+u32 pci_read_config(u16 bdf, u16 address, unsigned int size);
+void pci_write_config(u16 bdf, u16 address, u32 value, unsigned int size);
+
 const struct jailhouse_pci_device *
 pci_get_assigned_device(const struct cell *cell, u16 bdf);
 

diff --git a/hypervisor/pci.c b/hypervisor/pci.c
index d05999cb5cb2e02f35cbc066e0cf9a7c267d9260..47a612035146d267fac5ab1ff2def2959f1a52f8 100644 (file)
--- a/hypervisor/pci.c
+++ b/hypervisor/pci.c
@@ -5,6 +5,7 @@
  *
  * Authors:
  *  Ivan Kolchin <ivan.kolchin@siemens.com>
+ *  Jan Kiszka <jan.kiszka@siemens.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2.  See
  * the COPYING file in the top-level directory.
@@ -55,6 +56,57 @@ static const struct pci_cfg_access bridge_write_access[] = {
 static void *pci_space;
 static u64 pci_mmcfg_addr;
 static u32 pci_mmcfg_size;
+static u8 end_bus;
+
+static void *pci_get_device_mmcfg_base(u16 bdf)
+{
+       return pci_space + ((unsigned long)bdf << 12);
+}
+
+/**
+ * pci_read_config() - Read from PCI config space
+ * @bdf:       16-bit bus/device/function ID of target
+ * @address:   Config space access address
+ * @size:      Access size (1, 2 or 4 bytes)
+ *
+ * Return: read value
+ */
+u32 pci_read_config(u16 bdf, u16 address, unsigned int size)
+{
+       void *mmcfg_addr = pci_get_device_mmcfg_base(bdf) + address;
+
+       if (!pci_space || PCI_BUS(bdf) > end_bus)
+               return arch_pci_read_config(bdf, address, size);
+
+       if (size == 1)
+               return mmio_read8(mmcfg_addr);
+       else if (size == 2)
+               return mmio_read16(mmcfg_addr);
+       else
+               return mmio_read32(mmcfg_addr);
+}
+
+/**
+ * pci_write_config() - Write to PCI config space
+ * @bdf:       16-bit bus/device/function ID of target
+ * @address:   Config space access address
+ * @value:     Value to be written
+ * @size:      Access size (1, 2 or 4 bytes)
+ */
+void pci_write_config(u16 bdf, u16 address, u32 value, unsigned int size)
+{
+       void *mmcfg_addr = pci_get_device_mmcfg_base(bdf) + address;
+
+       if (!pci_space || PCI_BUS(bdf) > end_bus)
+               return arch_pci_write_config(bdf, address, value, size);
+
+       if (size == 1)
+               mmio_write8(mmcfg_addr, value);
+       else if (size == 2)
+               mmio_write16(mmcfg_addr, value);
+       else
+               mmio_write32(mmcfg_addr, value);
+}
 
 /**
  * pci_get_assigned_device() - Look up device owned by a cell
@@ -213,6 +265,8 @@ int pci_init(void)
        if (!pci_space)
                return -ENOMEM;
 
+       end_bus = mcfg->alloc_structs[0].end_bus;
+
        return page_map_create(&hv_paging_structs,
                               mcfg->alloc_structs[0].base_addr,
                               pci_mmcfg_size, (unsigned long)pci_space,