linux-toradex.git/arch/powerpc/kernel/pci_32.c, branch v6.16

mm/memblock: add memblock_alloc_or_panic interface

2025-01-26T04:22:38+00:00

Before SLUB initialization, various subsystems used memblock_alloc to
allocate memory.  In most cases, when memory allocation fails, an
immediate panic is required.  To simplify this behavior and reduce
repetitive checks, introduce `memblock_alloc_or_panic`.  This function
ensures that memory allocation failures result in a panic automatically,
improving code readability and consistency across subsystems that require
this behavior.

[guoweikang.kernel@gmail.com: arch/s390: save_area_alloc default failure behavior changed to panic]
  Link: https://lkml.kernel.org/r/20250109033136.2845676-1-guoweikang.kernel@gmail.com
  Link: https://lore.kernel.org/lkml/Z2fknmnNtiZbCc7x@kernel.org/
Link: https://lkml.kernel.org/r/20250102072528.650926-1-guoweikang.kernel@gmail.com
Signed-off-by: Guo Weikang 
Acked-by: Geert Uytterhoeven 	[m68k]
Reviewed-by: Alexander Gordeev 	[s390]
Acked-by: Mike Rapoport (Microsoft) 
Cc: Alexander Gordeev 
Signed-off-by: Andrew Morton

powerpc/pci: Add option for using pci_to_OF_bus_map

2023-02-07T09:15:23+00:00

The "pci-OF-bus-map" property was declared deprecated in 2006 [1] and to
the best of everyone's knowledge is not used by anything anymore [2].

The creation of the property was disabled on powermac (arch/powerpc) in
2005 by commit 35499c0195e4 ("powerpc: Merge in 64-bit powermac
support."). But it is still created by default on CHRP.

On powermac the actual map (pci_to_OF_bus_map) is still used by default,
even though the device tree property is not created.

Add an option to enable/disable use of the pci_to_OF_bus_map, and
creation of the property (on CHRP).

Disabling the option allows enabling CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT
which allows "normal" bus numbering and more than 256 buses, like 64-bit
and other architectures.

Mark the new option as default n, the intention is that the option and
the code will be removed in a future release.

[1]: https://lore.kernel.org/linuxppc-dev/1148016268.13249.14.camel@localhost.localdomain/
[2]: https://lore.kernel.org/all/575f239205e8635add81c9f902b7d9db7beb83ea.camel@kernel.crashing.org/

Signed-off-by: Pali Rohár 
[mpe: Reword commit & help text, shrink option name, rework to fix build errors]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20230206113902.1857123-1-mpe@ellerman.id.au

powerpc/pci: Enable PCI domains in /proc when PCI bus numbers are not unique

2022-08-25T07:47:08+00:00

On 32-bit powerpc systems with more PCIe controllers and more PCI
domains, where on more PCI domains are same PCI numbers, when kernel is
compiled with CONFIG_PROC_FS=y and
CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT=y options, kernel prints
"proc_dir_entry 'pci/01' already registered" error message.

  proc_dir_entry 'pci/01' already registered
  WARNING: CPU: 0 PID: 1 at fs/proc/generic.c:377 proc_register+0x1a8/0x1ac
  ...
  NIP proc_register+0x1a8/0x1ac
  LR  proc_register+0x1a8/0x1ac
  Call Trace:
    proc_register+0x1a8/0x1ac (unreliable)
    _proc_mkdir+0x78/0xa4
    pci_proc_attach_device+0x11c/0x168
    pci_proc_init+0x80/0x98
    do_one_initcall+0x80/0x284
    kernel_init_freeable+0x1f4/0x2a0
    kernel_init+0x24/0x150
    ret_from_kernel_thread+0x5c/0x64

This regression started appearing after commit
566356813082 ("powerpc/pci: Add config option for using all 256 PCI
buses") in case in each mPCIe slot is connected PCIe card and therefore
PCI bus 1 is populated in for every PCIe controller / PCI domain.

The reason is that PCI procfs code expects that when PCI bus numbers are
not unique across all PCI domains, function pci_proc_domain() returns
true for domain dependent buses.

Fix this issue by setting PCI_ENABLE_PROC_DOMAINS and
PCI_COMPAT_DOMAIN_0 flags for 32-bit powerpc code when
CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT is enabled. Same approach is
already implemented for 64-bit powerpc code (where PCI bus numbers are
always domain dependent).

Fixes: 566356813082 ("powerpc/pci: Add config option for using all 256 PCI buses")
Signed-off-by: Pali Rohár 
[mpe: Trim change log oops message]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220820115113.30581-1-pali@kernel.org

powerpc/pci: Add config option for using all 256 PCI buses

2022-07-27T11:36:04+00:00

By default on PPC32 PCI bus numbers are unique across all PCI domains.
So a system could have only 256 PCI buses independently of available PCI
domains.

This is due to filling DT property pci-OF-bus-map which does not support
a multi-domain setup.

On all powerpc platforms except chrp and powermac there is no DT
property pci-OF-bus-map anymore and therefore it is possible on
non-chrp/powermac platforms to avoid this limitation of maximum number
of 256 PCI buses in a system even on multi-domain setup.

But avoiding this limitation would mean that all PCI and PCIe devices
would be present on completely different BDF addresses as every PCI
domain starts numbering PCI bueses from zero (instead of the last bus
number of previous enumerated PCI domain). Such change could break
existing software which expects fixed PCI bus numbers.

So add a new config option CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT which
enables this change. By default it is disabled. It causes the initial
value of hose->first_busno to be zero.

Signed-off-by: Pali Rohár 
[mpe: Minor change log wording]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220706104308.5390-6-pali@kernel.org

powerpc/pci: Disable filling pci-OF-bus-map for non-chrp/powermac

2022-07-27T11:36:04+00:00

Creating or filling pci-OF-bus-map property in the device-tree is
deprecated since May 2006 [1] and was used only in old platforms like
PowerMac.

Currently kernel code handles it only for chrp and powermac code. So
completely disable filling pci-OF-bus-map property for non-chrp and
non-powermac platforms.

[1] - https://lore.kernel.org/linuxppc-dev/1148016268.13249.14.camel@localhost.localdomain/

Signed-off-by: Pali Rohár 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220706104308.5390-5-pali@kernel.org

powerpc/pci: Hide pci_create_OF_bus_map() for non-chrp code

2022-07-27T11:36:03+00:00

Function pci_create_OF_bus_map() is used only in chrp code.
So hide it from all other platforms.

Signed-off-by: Pali Rohár 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220706104308.5390-4-pali@kernel.org

powerpc/pci: Make pcibios_make_OF_bus_map() static

2022-07-27T11:36:03+00:00

Function pcibios_make_OF_bus_map() is used only in pci_32.c. So make it
static.

Signed-off-by: Pali Rohár 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220706104308.5390-3-pali@kernel.org

powerpc/pci: Hide pci_device_from_OF_node() for non-powermac code

2022-07-27T11:36:03+00:00

Function pci_device_from_OF_node() is used only in powermac code. So
hide it from all other platforms.

Signed-off-by: Pali Rohár 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220706104308.5390-2-pali@kernel.org

powerpc: Remove asm/prom.h from all files that don't need it

2022-05-08T12:15:04+00:00

Several files include asm/prom.h for no reason.

Clean it up.

Signed-off-by: Christophe Leroy 
[mpe: Drop change to prom_parse.c as reported by lkp@intel.com]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/7c9b8fda63dcf63e1b28f43e7ebdb95182cbc286.1646767214.git.christophe.leroy@csgroup.eu

powerpc/kernel: Add __init attribute to eligible functions

2021-12-23T11:33:10+00:00

Some functions defined in `arch/powerpc/kernel` (and one in `arch/powerpc/
kexec`) are deserving of an `__init` macro attribute. These functions are
only called by other initialization functions and therefore should inherit
the attribute.
Also, change function declarations in header files to include `__init`.

Signed-off-by: Nick Child 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20211216220035.605465-2-nick.child@ibm.com