[igt-dev] [PATCH i-g-t v5 2/5] lib/igt_device: add igt_device_map_pci_bar_region

Daniel Mrzyglod
2019-05-09T12:39:26Z

This function use sysfs to map particular mmio region.
fd of opened device point us for specific pci device.

Signed-off-by: Daniel Mrzyglod <daniel.t.mrzyglod@intel.com>
---
lib/igt_device.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
lib/igt_device.h | 1 +
2 files changed, 45 insertions(+)

diff --git a/lib/igt_device.c b/lib/igt_device.c
index 88f35cad..b456b936 100644
--- a/lib/igt_device.c
+++ b/lib/igt_device.c
@@ -227,3 +227,47 @@ struct pci_device *igt_device_get_pci_device(int fd)

return pci_dev;
}
+
+/**
+ * igt_device_map_pci_bar_region:
+ *
+ * @fd: the device
+ * @mmio_bar: bar to be mapped
+ * @mmio_size: bar size
+ *
+ * Returns:
+ * The pointer for mmapped bar
+ */
+void *igt_device_map_pci_bar_region(int fd, int mmio_bar, int mmio_size)
+{
+ struct igt_pci_addr pci_addr;
+ char *filepath = NULL;
+ char *pci_string = NULL;
+ int newfd;
+ void *igt_mmio;
+
+ if (igt_device_get_pci_addr(fd, &pci_addr)) {
+ igt_warn("Unable to find device PCI address\n");
+ return NULL;
+ }
+
+ asprintf(&pci_string, "%.4x:%.2x:%.2x.%.1x",
+ pci_addr.domain, pci_addr.bus, pci_addr.device,
+ pci_addr.function);
+
+
+ asprintf(&filepath, "/sys/devices/pci%.4x:%.2x/%s/resource%.1x",
+ pci_addr.domain, pci_addr.bus, pci_string, mmio_bar);
+
+ newfd = open(filepath, O_RDWR | O_SYNC);
+ igt_mmio = mmap(0, mmio_size, PROT_READ | PROT_WRITE, MAP_SHARED,
+ newfd, 0);
+ free(filepath);
+ close(newfd);
+ igt_warn_on_f(igt_mmio == MAP_FAILED,
+ "Couldn't map MMIO region %s BAR %d\n",
+ pci_string, mmio_bar);
+ free(pci_string);
+
+ return igt_mmio;
+}
diff --git a/lib/igt_device.h b/lib/igt_device.h
index 278ba7a9..c4188e96 100644
--- a/lib/igt_device.h
+++ b/lib/igt_device.h
@@ -33,5 +33,6 @@ void igt_device_drop_master(int fd);

int igt_device_get_card_index(int fd);
struct pci_device *igt_device_get_pci_device(int fd);
+void *igt_device_map_pci_bar_region(int fd, int mmio_bar, int mmio_size);

#endif /* __IGT_DEVICE_H__ */