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The pcibios_init() function for PowerPC 64 currently calls pci_bus_add_devices() before pcibios_resource_survey(). This means that at boot time, when the pcibios_bus_add_device() hooks are called by pci_bus_add_devices(), device resources have not been allocated and they are unable to perform EEH setup, so a separate pass is needed. This patch adjusts that order so that it will become possible to consolidate the EEH setup work into a single location. The only functional change is to execute pcibios_resource_survey() (excepting ppc_md.pcibios_fixup(), see below) before pci_bus_add_devices() instead of after it. Because pcibios_scan_phb() and pci_bus_add_devices() are called together in a loop, this must be broken into one loop for each call. Then the call to pcibios_resource_survey() is moved up in between them. This changes the ordering but because pcibios_resource_survey() also calls ppc_md.pcibios_fixup(), that call is extracted out into pcibios_init() to where pcibios_resource_survey() was, so that it is not moved. The only other caller of pcibios_resource_survey() is the PowerPC 32 version of pcibios_init(), and therefore, that is modified to call ppc_md.pcibios_fixup() right after pcibios_resource_survey() so that there is no functional change there at all. The re-arrangement will cause very few side-effects because at this stage in the boot, pci_bus_add_devices() does very little: - pci_create_sysfs_dev_files() does nothing (no sysfs yet) - pci_proc_attach_device() does nothing (no proc yet) - device_attach() does nothing (no drivers yet) This leaves only the pci_final_fixup calls, D3 support, and marking the device as added. Of those, only the pci_final_fixup calls have the potential to be affected by resource allocation. The only pci_final_fixup handlers that touch resources seem to be one for x86 (pci_amd_enable_64bit_bar()), and a PowerPC 32 platform driver (quirk_final_uli1575()), neither of which use this pcibios_init() function. Even if they did, it would almost certainly be a bug, under the current ordering, to rely on or make changes to resources before they were allocated. Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4506b0489eabd0921a3587d90bd44c7683f3472d.1565930772.git.sbobroff@linux.ibm.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.