pci: access to specific bits via sysfs

[dpdk.git] / lib / librte_eal / linuxapp / eal / eal_pci.c

diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
index 3b94b6f..b20c510 100644 (file)
--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
@@ -393,6 +393,96 @@ error:
        return -1;
 }
 
+#ifdef RTE_PCI_CONFIG
+static int
+pci_config_extended_tag(struct rte_pci_device *dev)
+{
+       struct rte_pci_addr *loc = &dev->addr;
+       char filename[PATH_MAX];
+       char buf[BUFSIZ];
+       FILE *f;
+
+       /* not configured, let it as is */
+       if (strncmp(RTE_PCI_EXTENDED_TAG, "on", 2) != 0 &&
+               strncmp(RTE_PCI_EXTENDED_TAG, "off", 3) != 0)
+               return 0;
+
+       rte_snprintf(filename, sizeof(filename),
+               SYSFS_PCI_DEVICES "/" PCI_PRI_FMT "/" "extended_tag",
+               loc->domain, loc->bus, loc->devid, loc->function);
+       f = fopen(filename, "rw+");
+       if (!f)
+               return -1;
+
+       fgets(buf, sizeof(buf), f);
+       if (strncmp(RTE_PCI_EXTENDED_TAG, "on", 2) == 0) {
+               /* enable Extended Tag*/
+               if (strncmp(buf, "on", 2) != 0) {
+                       fseek(f, 0, SEEK_SET);
+                       fputs("on", f);
+               }
+       } else {
+               /* disable Extended Tag */
+               if (strncmp(buf, "off", 3) != 0) {
+                       fseek(f, 0, SEEK_SET);
+                       fputs("off", f);
+               }
+       }
+       fclose(f);
+
+       return 0;
+}
+
+static int
+pci_config_max_read_request_size(struct rte_pci_device *dev)
+{
+       struct rte_pci_addr *loc = &dev->addr;
+       char filename[PATH_MAX];
+       char buf[BUFSIZ], param[BUFSIZ];
+       FILE *f;
+       /* size can be 128, 256, 512, 1024, 2048, 4096 */
+       uint32_t max_size = RTE_PCI_MAX_READ_REQUEST_SIZE;
+
+       /* not configured, let it as is */
+       if (!max_size)
+               return 0;
+
+       rte_snprintf(filename, sizeof(filename),
+               SYSFS_PCI_DEVICES "/" PCI_PRI_FMT "/" "max_read_request_size",
+                       loc->domain, loc->bus, loc->devid, loc->function);
+       f = fopen(filename, "rw+");
+       if (!f)
+               return -1;
+
+       fgets(buf, sizeof(buf), f);
+       rte_snprintf(param, sizeof(param), "%d", max_size);
+
+       /* check if the size to be set is the same as current */
+       if (strcmp(buf, param) == 0) {
+               fclose(f);
+               return 0;
+       }
+       fseek(f, 0, SEEK_SET);
+       fputs(param, f);
+       fclose(f);
+
+       return 0;
+}
+
+static void
+pci_config_space_set(struct rte_pci_device *dev)
+{
+       if (rte_eal_process_type() != RTE_PROC_PRIMARY)
+               return;
+
+       /* configure extended tag */
+       pci_config_extended_tag(dev);
+
+       /* configure max read request size */
+       pci_config_max_read_request_size(dev);
+}
+#endif
+
 static int
 pci_map_device(struct rte_pci_device *dev)
 {
@@ -460,6 +550,13 @@ rte_eal_pci_probe_one_driver(struct rte_pci_driver *dr, struct rte_pci_device *d
                }
 
                if (dr->drv_flags & RTE_PCI_DRV_NEED_MAPPING) {
+#ifdef RTE_PCI_CONFIG
+                       /*
+                        * Set PCIe config space for high performance.
+                        * Return value can be ignored.
+                        */
+                       pci_config_space_set(dev);
+#endif
                        /* map resources for devices that use igb_uio */
                        ret = pci_map_device(dev);
                        if (ret != 0)