[U-Boot] [PATCH 2/4] efi_loader: add udevice to EFI device-path mapping

Rob Clark
2017-07-21T18:43:37Z

Initially just supports "disk" type devices, but a real UEFI
implementation would expose input/output/display/etc with device-paths
as well, so we may eventually want to expand this for other uses.

Signed-off-by: Rob Clark <robdclark@gmail.com>
---
include/efi_loader.h | 9 +++
lib/efi_loader/Makefile | 1 +
lib/efi_loader/efi_devpath.c | 175 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 185 insertions(+)
create mode 100644 lib/efi_loader/efi_devpath.c

diff --git a/include/efi_loader.h b/include/efi_loader.h
index 812ec10e37..97d5e3d13d 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -145,6 +145,15 @@ extern void *efi_bounce_buffer;
#define EFI_LOADER_BOUNCE_BUFFER_SIZE (64 * 1024 * 1024)
#endif

+/*
+ * u-boot to EFI device mapping:
+ *
+ * TODO extend this for GOP and various other input/output
+ * devices which should also have an EFI devicepath?
+ */
+struct efi_device_path *efi_dp_from_dev(struct udevice *dev);
+struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part);
+
/* Convert strings from normal C strings to uEFI strings */
static inline void ascii2unicode(u16 *unicode, const char *ascii)
{
diff --git a/lib/efi_loader/Makefile b/lib/efi_loader/Makefile
index 9c67367df4..e191a3280b 100644
--- a/lib/efi_loader/Makefile
+++ b/lib/efi_loader/Makefile
@@ -22,3 +22,4 @@ obj-$(CONFIG_DM_VIDEO) += efi_gop.o
obj-$(CONFIG_PARTITIONS) += efi_disk.o
obj-$(CONFIG_NET) += efi_net.o
obj-$(CONFIG_GENERATE_SMBIOS_TABLE) += efi_smbios.o
+obj-$(CONFIG_DM) += efi_devpath.o
diff --git a/lib/efi_loader/efi_devpath.c b/lib/efi_loader/efi_devpath.c
new file mode 100644
index 0000000000..16b8edf899
--- /dev/null
+++ b/lib/efi_loader/efi_devpath.c
@@ -0,0 +1,175 @@
+/*
+ * EFI device path from u-boot device-model mapping
+ *
+ * (C) Copyright 2017 Rob Clark
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <blk.h>
+#include <dm.h>
+#include <usb.h>
+#include <mmc.h>
+#include <efi_loader.h>
+#include <inttypes.h>
+#include <part.h>
+#include <malloc.h>
+
+/* template END node: */
+const static struct efi_device_path END = {
+ .type = DEVICE_PATH_TYPE_END,
+ .sub_type = DEVICE_PATH_SUB_TYPE_END,
+ .length = sizeof(END),
+};
+
+/* template ROOT node, a fictional ACPI PNP device: */
+const static struct efi_device_path_acpi_path ROOT = {
+ .dp = {
+ .type = DEVICE_PATH_TYPE_ACPI_DEVICE,
+ .sub_type = DEVICE_PATH_SUB_TYPE_ACPI_DEVICE,
+ .length = sizeof(ROOT),
+ },
+ .hid = EISA_PNP_ID(0x1337),
+ .uid = 0,
+};
+
+
+/* size of device-path not including END node for device and all parents
+ * up to the root device.
+ */
+static unsigned dp_size(struct udevice *dev)
+{
+ if (!dev || !dev->driver)
+ return sizeof(ROOT);
+
+ switch (dev->driver->id) {
+ case UCLASS_ROOT:
+ case UCLASS_SIMPLE_BUS:
+ /* stop traversing parents at this point: */
+ return sizeof(ROOT);
+ case UCLASS_MMC:
+ return dp_size(dev->parent) + sizeof(struct efi_device_path_sd_mmc_path);
+ case UCLASS_MASS_STORAGE:
+ case UCLASS_USB_HUB:
+ return dp_size(dev->parent) + sizeof(struct efi_device_path_usb);
+ default:
+ /* just skip over unknown classes: */
+ return dp_size(dev->parent);
+ }
+}
+
+static void *dp_fill(void *buf, struct udevice *dev)
+{
+ if (!dev || !dev->driver)
+ return buf;
+
+ switch (dev->driver->id) {
+ case UCLASS_ROOT:
+ case UCLASS_SIMPLE_BUS: {
+ /* stop traversing parents at this point: */
+ struct efi_device_path_acpi_path *adp = buf;
+ *adp = ROOT;
+ return &adp[1];
+ }
+ case UCLASS_MMC: {
+ struct efi_device_path_sd_mmc_path *sddp =
+ dp_fill(buf, dev->parent);
+ struct mmc *mmc = mmc_get_mmc_dev(dev);
+ struct blk_desc *desc = mmc_get_blk_desc(mmc);
+
+ sddp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
+ sddp->dp.sub_type = (desc->if_type == IF_TYPE_MMC) ?
+ DEVICE_PATH_SUB_TYPE_MSG_MMC :
+ DEVICE_PATH_SUB_TYPE_MSG_SD;
+ sddp->dp.length = sizeof(*sddp);
+ sddp->slot_number = 0; // XXX ???
+
+ return &sddp[1];
+ }
+ case UCLASS_MASS_STORAGE:
+ case UCLASS_USB_HUB: {
+ struct efi_device_path_usb *udp =
+ dp_fill(buf, dev->parent);
+
+ udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
+ udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
+ udp->dp.length = sizeof(*udp);
+ udp->parent_port_number = 0; // XXX ???
+ udp->usb_interface = 0; // XXX ???
+
+ return &udp[1];
+ }
+ default:
+ debug("unhandled device class: %s (%u)\n",
+ dev->name, dev->driver->id);
+ return dp_fill(buf, dev->parent);
+ }
+}
+
+/* Construct a device-path from a device: */
+struct efi_device_path *efi_dp_from_dev(struct udevice *dev)
+{
+ void *buf, *start;
+
+ start = buf = calloc(1, dp_size(dev) + sizeof(END));
+ buf = dp_fill(buf, dev);
+ *((struct efi_device_path *)buf) = END;
+
+ return start;
+}
+
+/* Construct a device-path from a partition on a blk device: */
+struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part)
+{
+ disk_partition_t info;
+ unsigned dpsize;
+ void *buf, *start;
+
+ dpsize = dp_size(desc->bdev->parent) + sizeof(END);
+
+ if (desc->part_type == PART_TYPE_ISO) {
+ dpsize += sizeof(struct efi_device_path_cdrom_path);
+ } else {
+ dpsize += sizeof(struct efi_device_path_hard_drive_path);
+ }
+
+ start = buf = calloc(1, dpsize);
+
+ buf = dp_fill(buf, desc->bdev->parent);
+
+ part_get_info(desc, part, &info);
+
+ if (desc->part_type == PART_TYPE_ISO) {
+ struct efi_device_path_cdrom_path *cddp = buf;
+
+ cddp->boot_entry = part - 1;
+ cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
+ cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
+ cddp->dp.length = sizeof (*cddp);
+ cddp->partition_start = info.start;
+ cddp->partition_end = info.size;
+
+ buf = &cddp[1];
+ } else {
+ struct efi_device_path_hard_drive_path *hddp = buf;
+
+ hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
+ hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
+ hddp->dp.length = sizeof (*hddp);
+ hddp->partition_number = part - 1;
+ hddp->partition_start = info.start;
+ hddp->partition_end = info.size;
+ if (desc->part_type == PART_TYPE_EFI)
+ hddp->partmap_type = 2;
+ else
+ hddp->partmap_type = 1;
+ hddp->signature_type = 0;
+
+ buf = &hddp[1];
+ }
+
+ *((struct efi_device_path *)buf) = END;
+
+ return start;
+}
--
2.13.0