[PATCH 00/27] dm: Change the way sequence numbers are implemented
Simon Glass
sjg at chromium.org
Mon Nov 30 02:53:35 CET 2020
At present each device has two sequence numbers, with 'req_seq' being
set up at bind time and 'seq' at probe time. The idea is that devices
can 'request' a sequence number and then the conflicts are resolved when
the device is probed.
This makes things complicated in a few cases, since we don't really know
(at bind time) what the sequence number will end up being. We want to
honour the bind-time requests if at all possible, but in fact the only
source of these at present is the devicetree aliases.
Apart from the obvious need for sequence numbers to supports U-Boot's
numbering on devices on the command line, the current scheme was
designed to:
- avoid calculating the sequence number until it is needed, to save
execution time
- allow multiple devices to obtain a particular sequence number as they
are probed and removed
- retain a record of the 'requested' sequence number even if it turns out
that a device could not get it (to allow debugging and retrying)
After some years using the current scheme it seems on balance that these
goals don't have as much merit as first thought. The first point would
be persuasive except that we end up reading the devicetree aliases at
bind-time anyway. So the work of resolving the sequence numbers during
probing is not that great. The second point hasn't really been an issue,
as there is typically no contention for sequence numbers (boards tend to
allocate them statically in the devicetree). Re the third point, we can
often figure out what was requested by looking at aliases, and in the
cases where we can't, it doesn't seem to matter much.
Since we have the devicetree available at bind time, we may as well just
use it, in the hope that the required processing will turn out to be
useful later (i.e. the device actually gets used). In addition, it is
simpler to use a single sequence number, since it avoids confusion and
some extra code.
This series moves U-Boot to use a single, bind-time sequence number. All
uclasses with the DM_UC_FLAG_SEQ_ALIAS flag enabled will assign sequence
numbers to their devices, so that as soon as a device is bound, it has a
sequence number. If a devicetree alias provides the number, it will be
used. Otherwise, during initial binding, the first free number is used.
For ad-hoc calls to device_bind() afterwards (e.g. from driver code), the
sequence is set to the maximum sequence number for the uclass + 1.
Apart from the simplicity gains, overall these changes seem to reduce the
number of tweaks and workarounds needed to get the desired behaviour.
However there will certainly be some problems created, so board
maintainers should test this out.
Simon Glass (27):
linker_lists: Fix alignment issue
efi: Drop unwanted message in efi_uc_destroy()
dm: Avoid accessing seq directly
dm: core: Update uclass_find_next_free_req_seq() args
dm: core: Add a new sequence number for devices
dm: test: Add support for new sequence numbers
dm: core: Switch binding to use new sequence numbers
dm: Fix return value in dev_read_alias_seq()
dm: test: Drop assumptions of no sequence numbers
octeon: Don't attempt to set the sequence number
i2c: Update for new sequence numbers
net: Update to use new sequence numbers
pci: Update to use new sequence numbers
spi: Update for new sequence numbers
usb: ehci-mx6: Drop assignment of sequence number
usb: Update for new sequence numbers
x86: Drop unnecessary mp_init logic
x86: Simplify acpi_device_infer_name()
gpio: Update for new sequence numbers
pinctrl: Update for new sequence numbers
dm: Switch over to use new sequence number for dev_seq()
dm: Drop uclass_resolve_seq()
dm: Drop the unused arg in uclass_find_device_by_seq()
dm: core: Simplify uclass_find_next_free_req_seq()
cmd: Drop use of old sequence numbers in commands
dm: core: Drop seq and req_seq
dm: Update documentation for new sequence numbers
arch/Kconfig | 11 +++
arch/arm/include/asm/mach-imx/mxc_i2c.h | 2 +-
arch/arm/mach-k3/am6_init.c | 2 +-
arch/arm/mach-k3/j721e_init.c | 2 +-
arch/arm/mach-k3/sysfw-loader.c | 2 +-
arch/sandbox/dts/test.dts | 2 +-
arch/x86/cpu/apollolake/cpu.c | 2 +-
arch/x86/cpu/broadwell/cpu_full.c | 2 +-
arch/x86/cpu/ivybridge/model_206ax.c | 2 +-
arch/x86/cpu/mp_init.c | 23 ++---
arch/x86/include/asm/mp.h | 2 +-
board/xilinx/versal/board.c | 12 +--
board/xilinx/zynqmp/zynqmp.c | 12 +--
cmd/axi.c | 6 +-
cmd/cpu.c | 2 +-
cmd/i2c.c | 6 +-
cmd/misc.c | 2 +-
cmd/osd.c | 6 +-
cmd/pci.c | 7 +-
cmd/pmic.c | 4 +-
cmd/remoteproc.c | 2 +-
cmd/w1.c | 4 +-
doc/api/linker_lists.rst | 62 ++++++++++++
doc/driver-model/design.rst | 58 +++++++-----
drivers/core/device-remove.c | 1 -
drivers/core/device.c | 52 ++++------
drivers/core/dump.c | 4 +-
drivers/core/read.c | 4 +-
drivers/core/root.c | 21 ++++-
drivers/core/uclass.c | 115 ++++++++++-------------
drivers/gpio/imx_rgpio2p.c | 2 +-
drivers/gpio/iproc_gpio.c | 2 +-
drivers/gpio/mvebu_gpio.c | 2 +-
drivers/gpio/mxc_gpio.c | 2 +-
drivers/gpio/octeon_gpio.c | 2 +-
drivers/gpio/vybrid_gpio.c | 2 +-
drivers/i2c/ast_i2c.c | 4 +-
drivers/i2c/davinci_i2c.c | 2 +-
drivers/i2c/designware_i2c_pci.c | 16 +---
drivers/i2c/exynos_hs_i2c.c | 2 +-
drivers/i2c/i2c-gpio.c | 2 +-
drivers/i2c/i2c-uclass.c | 8 +-
drivers/i2c/i2c-versatile.c | 5 -
drivers/i2c/imx_lpi2c.c | 12 +--
drivers/i2c/intel_i2c.c | 12 +--
drivers/i2c/lpc32xx_i2c.c | 6 +-
drivers/i2c/muxes/i2c-mux-uclass.c | 4 +-
drivers/i2c/mvtwsi.c | 4 +-
drivers/i2c/mxc_i2c.c | 10 +-
drivers/i2c/nx_i2c.c | 2 +-
drivers/i2c/octeon_i2c.c | 3 +-
drivers/i2c/s3c24x0_i2c.c | 2 +-
drivers/i2c/tegra_i2c.c | 5 +-
drivers/mmc/fsl_esdhc_imx.c | 4 +-
drivers/mmc/octeontx_hsmmc.c | 2 -
drivers/mtd/spi/sandbox.c | 4 +-
drivers/net/dwc_eth_qos.c | 2 +-
drivers/net/fec_mxc.c | 7 +-
drivers/net/fsl-mc/mc.c | 2 +-
drivers/net/fsl_mcdmafec.c | 2 +-
drivers/net/ftgmac100.c | 2 +-
drivers/net/higmacv300.c | 2 +-
drivers/net/mcffec.c | 2 +-
drivers/net/octeontx/nicvf_main.c | 9 +-
drivers/net/octeontx/smi.c | 3 +-
drivers/net/octeontx2/nix.c | 2 +-
drivers/net/octeontx2/rvu_pf.c | 6 +-
drivers/net/xilinx_axi_emac.c | 2 +-
drivers/net/xilinx_emaclite.c | 2 +-
drivers/net/zynq_gem.c | 2 +-
drivers/pci/pci-aardvark.c | 2 +-
drivers/pci/pci-uclass.c | 42 ++++-----
drivers/pci/pci_auto.c | 6 +-
drivers/pci/pcie_dw_mvebu.c | 6 +-
drivers/pci/pcie_dw_ti.c | 6 +-
drivers/pci/pcie_ecam_generic.c | 2 +-
drivers/pci/pcie_fsl.c | 16 ++--
drivers/pci/pcie_intel_fpga.c | 2 +-
drivers/pci/pcie_layerscape_fixup.c | 4 +-
drivers/pci/pcie_layerscape_gen4.c | 10 +-
drivers/pci/pcie_layerscape_gen4_fixup.c | 2 +-
drivers/pci/pcie_layerscape_rc.c | 12 +--
drivers/pci/pcie_mediatek.c | 2 +-
drivers/pci/pcie_rockchip.c | 6 +-
drivers/pinctrl/exynos/pinctrl-exynos.c | 2 +-
drivers/serial/serial_mcf.c | 2 +-
drivers/serial/serial_s5p.c | 2 +-
drivers/spi/altera_spi.c | 2 +-
drivers/spi/cf_spi.c | 12 +--
drivers/spi/fsl_dspi.c | 8 +-
drivers/spi/fsl_espi.c | 2 +-
drivers/spi/octeon_spi.c | 2 +-
drivers/spi/pic32_spi.c | 4 +-
drivers/spi/rk_spi.c | 1 -
drivers/spi/sandbox_spi.c | 2 +-
drivers/spi/spi-uclass.c | 4 +-
drivers/spi/tegra114_spi.c | 2 +-
drivers/spi/tegra20_sflash.c | 2 +-
drivers/spi/tegra20_slink.c | 2 +-
drivers/spi/tegra210_qspi.c | 2 +-
drivers/spi/xilinx_spi.c | 2 +-
drivers/spi/zynq_qspi.c | 2 +-
drivers/spi/zynq_spi.c | 2 +-
drivers/usb/gadget/max3420_udc.c | 2 +-
drivers/usb/host/ehci-mx5.c | 2 +-
drivers/usb/host/ehci-mx6.c | 14 ++-
drivers/usb/host/ehci-omap.c | 2 +-
drivers/usb/host/ehci-vf.c | 8 +-
drivers/usb/host/usb-sandbox.c | 2 +-
drivers/usb/host/usb-uclass.c | 6 +-
drivers/video/vidconsole-uclass.c | 4 +-
drivers/virtio/virtio-uclass.c | 2 +-
drivers/watchdog/ast_wdt.c | 2 +-
drivers/watchdog/at91sam9_wdt.c | 2 +-
drivers/watchdog/cdns_wdt.c | 2 +-
drivers/watchdog/omap_wdt.c | 2 +-
drivers/watchdog/orion_wdt.c | 2 +-
drivers/watchdog/sbsa_gwdt.c | 2 +-
drivers/watchdog/sp805_wdt.c | 2 +-
drivers/watchdog/tangier_wdt.c | 2 +-
drivers/watchdog/xilinx_tb_wdt.c | 2 +-
drivers/watchdog/xilinx_wwdt.c | 2 +-
include/asm-generic/global_data.h | 2 +
include/configs/sandbox.h | 2 +-
include/dm/device.h | 32 +++----
include/dm/uclass-internal.h | 34 +++----
include/dm/uclass.h | 15 +--
include/linker_lists.h | 3 +-
include/pci.h | 2 +-
include/spi.h | 2 +-
lib/acpi/acpi_device.c | 27 +-----
lib/efi_driver/efi_uclass.c | 1 -
lib/efi_loader/efi_device_path.c | 4 +-
net/eth-uclass.c | 24 +++--
test/dm/acpi.c | 6 +-
test/dm/blk.c | 3 -
test/dm/bus.c | 15 +--
test/dm/core.c | 19 ++++
test/dm/eth.c | 14 +--
test/dm/i2c.c | 3 -
test/dm/spi.c | 3 -
test/dm/test-fdt.c | 100 ++++++++++++--------
test/dm/test-main.c | 6 ++
143 files changed, 583 insertions(+), 569 deletions(-)
--
2.29.2.454.gaff20da3a2-goog
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