1 files changed, 159 insertions, 0 deletions
diff --git a/sys/arch/amd64/pci/pci_resource.c b/sys/arch/amd64/pci/pci_resource.c
new file mode 100644
index 0000000..5ca597b
--- /dev/null
+++ b/sys/arch/amd64/pci/pci_resource.c
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/errno.h>
+#include <sys/syslog.h>
+#include <dev/pci/resource.h>
+#include <dev/pci/pci.h>
+#include <dev/pci/pciregs.h>
+
+// #define DEBUG 1
+
+#define pr_trace(fmt, ...) kprintf("pci: " fmt, ##__VA_ARGS__)
+#define pr_error(...) pr_trace(__VA_ARGS__)
+
+#if defined(DEBUG)
+#define pr_debug(...) pr_trace(__VA_ARGS__)
+#else
+#define pr_debug(...) __nothing
+#endif
+
+/*
+ * Enables bus mastering for a specific PCI device.
+ *
+ * @brp: Pointer to bus resource handle.
+ * @devp: Pointer to `pci_device' structure.
+ *
+ * XXX: If the bus resource is MMIO capable, PCI
+ *      memory space access will become set within
+ *      the command/status register
+ */
+int
+pcir_enable_dma(struct bus_resource *brp, void *devp)
+{
+    struct pci_device *dev = devp;
+    uint32_t tmp;
+
+    if (brp == NULL || dev == NULL) {
+        return -EINVAL;
+    }
+
+    /*
+     * Make sure that we are allowed to perform DMA. This
+     * will fail if the bus isn't DMA-capable or if DMA
+     * is disabled.
+     */
+    if (!ISSET(brp->sem, BUS_DMA)) {
+        pr_trace("Bus marked non DMA capable, DMA not enabled\n");
+        return -EACCES;
+    }
+
+    tmp = pci_readl(dev, PCIREG_CMDSTATUS);
+    tmp |= PCI_BUS_MASTERING;
+    tmp |= ISSET(brp->sem, BUS_MMIO);
+    pci_writel(dev, PCIREG_CMDSTATUS, tmp);
+    return 0;
+}
+
+/*
+ * Disables bus mastering for a specific PCI device.
+ *
+ * @brp: Pointer to bus resource handle.
+ * @devp: Pointer to `pci_device' structure.
+ *
+ * XXX: If the bus resource is not MMIO capable, PCI
+ *      memory space access will become unset within
+ *      the command/status register
+ */
+int
+pcir_disable_dma(struct bus_resource *brp, void *devp)
+{
+    struct pci_device *dev = devp;
+    uint32_t tmp;
+
+    if (brp == NULL || dev == NULL) {
+        return -EINVAL;
+    }
+
+    tmp = pci_readl(dev, PCIREG_CMDSTATUS);
+    tmp &= ~PCI_BUS_MASTERING;
+    tmp &= ~ISSET(brp->sem, BUS_MMIO);
+    pci_writel(dev, PCIREG_CMDSTATUS, tmp);
+    return 0;
+}
+
+int
+pcir_set_sem(struct bus_resource *brp, bus_sem_t sem)
+{
+    /*
+     * BUS_PIO and BUS_MMIO are two different things
+     * and must be mutually exclusive...
+     */
+    if (ISSET(sem, BUS_MMIO) && ISSET(sem, BUS_PIO)) {
+        pr_debug("Bad semantics (sem=%x)\n", sem);
+        return -EINVAL;
+    }
+
+    brp->sem |= sem;
+    return 0;
+}
+
+int
+pcir_clr_sem(struct bus_resource *brp, bus_sem_t sem)
+{
+    brp->sem &= ~sem;
+    return 0;
+}
+
+__unused int
+pcir_dma_alloc(struct bus_resource *brp, void *res)
+{
+    return 0;
+}
+
+__unused int
+pcir_dma_free(struct bus_resource *brp, void *p)
+{
+    return 0;
+}
+
+ssize_t
+pcir_dma_in(struct bus_resource *brp, void *p)
+{
+    return 0;
+}
+
+ssize_t
+pcir_dma_out(struct bus_resource *brp, void *p)
+{
+    return 0;
+}