Merge branch '2023-01-24-bootstd-allow-migration-from-distro_bootcmd-script'

To quote the author:
So far, standard boot does not replicate all the of the functionality
of the distro_bootcmd scripts. In particular it lacks some bootdevs and
some of the bootmeths are incomplete.

Also there is currently no internal mechanism to enumerate buses in order
to discover bootdevs, e.g. with USB.

This series addresses these shortcomings:

- Adds the concept of a 'bootdev hunter' to enumerate buses, etc. in an
  effort to find bootdevs of a certain priority
- Adds bootdevs for SCSI, IDE, NVMe, virtio, SPI flash
- Handles PXE and DHCP properly
- Supports reading the device tree with EFI and reading scripts from the
  network

It also tidies up label processing, so it is possible to use:

   bootflow scan mmc2

to scan just one MMC device (with BOOTSTD_FULL).

As before this implementation still relies on CONFIG_CMDLINE being
enabled, mostly for the network stack. Further work would be required to
disentangle that.

Quite a few tests are added but there are some gaps:

- SPI flash bootdev
- EFI FDT loading

Note that SATA works via SCSI (CONFIG_SCSI_AHCI) and does not use
driver model. Only pogo_v4 seems to be affected. Probably all thats is
needed is to call bootdev_setup_sibling_blk() in the Marvell SATA driver.

Also, while it would be possible to init MMC in a bootdev hunter, there is
no point since U-Boot always inits MMC on startup, if present.

With this series it should be possible to migrate boards to standard boot
by removing the inclusion of config_distro_bootcmd.h and instead adding
a suitable value for boot_targets to the environment, e.g.:

   boot_targets=mmc1 mmc0 nvme scsi usb pxe dhcp spi

Thus it is possible to boot automatically without scripts and boards can
use a text-based environment instead of the config.h files.

To demonstrate this, rockpro64-rk3399 is migrated to standard boot in this
series. Full migration could probably be automated using a script, similar
in concept to moveconfig:

   - obtain the board environment via 'make u-boot-initial-env'
   - get the value of "boot_targets"
   - drop config_distro_bootcmd.h from the config.h file
   - rebuild again to get the environment without distro scripts
   - write the environment (adding boot_targets) to board.env
   - remove CONFIG_EXTRA_ENV_SETTINGS from the config.h file

1 files changed, 38 insertions, 0 deletions

diff --git a/test/py/tests/test_dm.py b/test/py/tests/test_dm.py
index ea93061fdfa..68d4ea12235 100644
--- a/test/py/tests/test_dm.py
+++ b/test/py/tests/test_dm.py
@@ -16,6 +16,44 @@ def test_dm_compat(u_boot_console):
     for driver in drivers:
         assert driver in response
 
+    # check sorting - output looks something like this:
+    #  testacpi      0  [   ]   testacpi_drv          |-- acpi-test
+    #  testacpi      1  [   ]   testacpi_drv          |   `-- child
+    #  pci_emul_p    1  [   ]   pci_emul_parent_drv   |-- pci-emul2
+    #  pci_emul      5  [   ]   sandbox_swap_case_em  |   `-- emul2@1f,0
+
+    # The number of '|   ' and '--' matches indicate the indent level. We start
+    # checking sorting only after UCLASS_AXI_EMUL after which the names should
+    # be sorted.
+
+    response = u_boot_console.run_command('dm tree -s')
+    lines = response.split('\n')[2:]
+    stack = []   # holds where we were up to at the previous indent level
+    prev = ''    # uclass name of previous line
+    start = False
+    for line in lines:
+        indent = line.count('|   ') + ('--' in line)
+        cur = line.split()[0]
+        if not start:
+            if cur != 'axi_emul':
+                continue
+            start = True
+
+        # Handle going up or down an indent level
+        if indent > len(stack):
+            stack.append(prev)
+            prev = ''
+        elif indent < len(stack):
+            prev = stack.pop()
+
+        # Check that the current uclass name is not alphabetically before the
+        # previous one
+        if 'emul' not in cur and cur < prev:
+            print('indent', cur >= prev, indent, prev, cur, stack)
+            assert cur >= prev
+            prev = cur
+
+
 @pytest.mark.buildconfigspec('cmd_dm')
 def test_dm_drivers(u_boot_console):
     """Test that each driver in `dm compat` is also listed in `dm drivers`."""