libsel4vmmplatsupport/src/drivers/pci.c

/*
 * Copyright 2019, Data61
 * Commonwealth Scientific and Industrial Research Organisation (CSIRO)
 * ABN 41 687 119 230.
 *
 * This software may be distributed and modified according to the terms of
 * the BSD 2-Clause license. Note that NO WARRANTY is provided.
 * See "LICENSE_BSD2.txt" for details.
 *
 * @TAG(DATA61_BSD)
 */

/* VMM PCI Driver, which manages the host's PCI devices, and handles guest OS PCI config space
 * read & writes.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <sel4/sel4.h>
#include <pci/pci.h>
#include <pci/helper.h>

#include <sel4vmmplatsupport/drivers/pci.h>
#include <sel4vmmplatsupport/drivers/pci_helper.h>

#define NUM_DEVICES 32
#define NUM_FUNCTIONS 8

int vmm_pci_init(vmm_pci_space_t **space)
{
    vmm_pci_space_t *pci_space = (vmm_pci_space_t *)calloc(1, sizeof(vmm_pci_space_t));
    if (!pci_space) {
        ZF_LOGE("Failed to calloc memory for pci space");
        return -1;
    }

    for (int i = 0; i < NUM_DEVICES; i++) {
        for (int j = 0; j < NUM_FUNCTIONS; j++) {
            pci_space->bus0[i][j] = NULL;
        }
    }
    pci_space->conf_port_addr = 0;
    /* Define the initial PCI bridge */
    vmm_pci_device_def_t *bridge = calloc(1, sizeof(*bridge));
    if (!bridge) {
        ZF_LOGE("Failed to calloc memory for pci bridge");
        return -1;
    }
    define_pci_host_bridge(bridge);
    *space = pci_space;
    return vmm_pci_add_entry(pci_space, (vmm_pci_entry_t) {
        .cookie = bridge, .ioread = vmm_pci_mem_device_read, .iowrite = vmm_pci_entry_ignore_write
    }, NULL);
}

int vmm_pci_add_entry(vmm_pci_space_t *space, vmm_pci_entry_t entry, vmm_pci_address_t *addr)
{
    /* Find empty dev */
    for (int i = 0; i < 32; i++) {
        if (!space->bus0[i][0]) {
            /* Allocate an entry */
            space->bus0[i][0] = calloc(1, sizeof(entry));

            *space->bus0[i][0] = entry;
            /* Report addr if reqeusted */
            if (addr) {
                *addr = (vmm_pci_address_t) {
                    .bus = 0, .dev = i, .fun = 0
                };
            }
            ZF_LOGI("Adding virtual PCI device at %02x:%02x.%d", 0, i, 0);
            return 0;
        }
    }
    ZF_LOGE("No free device slot on bus 0 to add virtual pci device");
    return -1;
}

void make_addr_reg_from_config(uint32_t conf, vmm_pci_address_t *addr, uint8_t *reg)
{
    addr->bus = (conf >> 16) & MASK(8);
    addr->dev = (conf >> 11) & MASK(5);
    addr->fun = (conf >> 8) & MASK(3);
    *reg = conf & MASK(8);
}

vmm_pci_entry_t *find_device(vmm_pci_space_t *self, vmm_pci_address_t addr)
{
    if (addr.bus != 0 || addr.dev >= 32 || addr.fun >= 8) {
        return NULL;
    }
    return self->bus0[addr.dev][addr.fun];
}