linux-toradex.git/arch/powerpc/kernel/pci-common.c, branch v6.7

powerpc: Remove file parameter from phys_mem_access_prot()

2023-11-06T04:21:33+00:00

Remove 'file' parameter from struct machdep_calls.phys_mem_access_prot
and its implementation in pci_phys_mem_access_prot(). The file is not
used on PowerPC. By removing it, a later patch can simplify fbdev's
mmap code, which uses phys_mem_access_prot() on PowerPC.

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Arnd Bergmann 
[mpe: Rebase on unrelated changes to phys_mem_access_prot()]
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230922080636.26762-5-tzimmermann@suse.de

powerpc: Drop zalloc_maybe_bootmem()

2023-08-24T12:33:16+00:00

The only callers of zalloc_maybe_bootmem() are PCI setup routines. These
used to be called early during boot before slab setup, and also during
runtime due to hotplug.

But commit 5537fcb319d0 ("powerpc/pci: Add ppc_md.discover_phbs()")
moved the boot-time calls later, after slab setup, meaning there's no
longer any need for zalloc_maybe_bootmem(), kzalloc() can be used in all
cases.

Reviewed-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230823055430.752550-1-mpe@ellerman.id.au

PCI: Introduce pci_dev_for_each_resource()

2023-04-04T15:43:52+00:00

Instead of open-coding it everywhere introduce a tiny helper that can be
used to iterate over each resource of a PCI device, and convert the most
obvious users into it.

While at it drop doubled empty line before pdev_sort_resources().

No functional changes intended.

Suggested-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20230330162434.35055-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mika Westerberg 
Signed-off-by: Andy Shevchenko 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Krzysztof Wilczyński

powerpc/pci-common: Fix refcount bug for 'phb->dn'

2022-09-05T07:30:29+00:00

In pcibios_alloc_controller(), 'phb' is allocated and escaped into
global 'hose_list'. So we should call of_node_get() when a new reference
created into 'phb->dn'. And when phb is freed, we should call
of_node_put() on it.

NOTE: This function is called in the iteration of for_each_xx in
chrp_find_bridges() and pSeries_discover_phbs(). If there is no
of_node_get(), the object may be prematurely freed.

Signed-off-by: Liang He 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220702022936.266146-1-windhl@126.com

powerpc/pci: Fix get_phb_number() locking

2022-08-15T06:56:14+00:00

The recent change to get_phb_number() causes a DEBUG_ATOMIC_SLEEP
warning on some systems:

  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper
  preempt_count: 1, expected: 0
  RCU nest depth: 0, expected: 0
  1 lock held by swapper/1:
   #0: c157efb0 (hose_spinlock){+.+.}-{2:2}, at: pcibios_alloc_controller+0x64/0x220
  Preemption disabled at:
  [<00000000>] 0x0
  CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0-yocto-standard+ #1
  Call Trace:
  [d101dc90] [c073b264] dump_stack_lvl+0x50/0x8c (unreliable)
  [d101dcb0] [c0093b70] __might_resched+0x258/0x2a8
  [d101dcd0] [c0d3e634] __mutex_lock+0x6c/0x6ec
  [d101dd50] [c0a84174] of_alias_get_id+0x50/0xf4
  [d101dd80] [c002ec78] pcibios_alloc_controller+0x1b8/0x220
  [d101ddd0] [c140c9dc] pmac_pci_init+0x198/0x784
  [d101de50] [c140852c] discover_phbs+0x30/0x4c
  [d101de60] [c0007fd4] do_one_initcall+0x94/0x344
  [d101ded0] [c1403b40] kernel_init_freeable+0x1a8/0x22c
  [d101df10] [c00086e0] kernel_init+0x34/0x160
  [d101df30] [c001b334] ret_from_kernel_thread+0x5c/0x64

This is because pcibios_alloc_controller() holds hose_spinlock but
of_alias_get_id() takes of_mutex which can sleep.

The hose_spinlock protects the phb_bitmap, and also the hose_list, but
it doesn't need to be held while get_phb_number() calls the OF routines,
because those are only looking up information in the device tree.

So fix it by having get_phb_number() take the hose_spinlock itself, only
where required, and then dropping the lock before returning.
pcibios_alloc_controller() then needs to take the lock again before the
list_add() but that's safe, the order of the list is not important.

Fixes: 0fe1e96fef0a ("powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias")
Reported-by: Guenter Roeck 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220815065550.1303620-1-mpe@ellerman.id.au

powerpc/pci: Fix PHB numbering when using opal-phbid

2022-08-02T12:30:06+00:00

The recent change to the PHB numbering logic has a logic error in the
handling of "ibm,opal-phbid".

When an "ibm,opal-phbid" property is present, &prop is written to and
ret is set to zero.

The following call to of_alias_get_id() is skipped because ret == 0.

But then the if (ret >= 0) is true, and the body of that if statement
sets prop = ret which throws away the value that was just read from
"ibm,opal-phbid".

Fix the logic by only doing the ret >= 0 check in the of_alias_get_id()
case.

Fixes: 0fe1e96fef0a ("powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias")
Reviewed-by: Pali Rohár 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220802105723.1055178-1-mpe@ellerman.id.au

powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias

2022-07-28T06:22:13+00:00

Other Linux architectures use DT property 'linux,pci-domain' for
specifying fixed PCI domain of PCI controller specified in Device-Tree.

And lot of Freescale powerpc boards have defined numbered pci alias in
Device-Tree for every PCIe controller which number specify preferred PCI
domain.

So prefer usage of DT property 'linux,pci-domain' (via function
of_get_pci_domain_nr()) and DT pci alias (via function
of_alias_get_id()) on powerpc architecture for assigning PCI domain to
PCI controller.

Fixes: 63a72284b159 ("powerpc/pci: Assign fixed PHB number based on device-tree properties")
Signed-off-by: Pali Rohár 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220706102148.5060-2-pali@kernel.org

powerpc: Fix all occurences of duplicate words

2022-07-25T02:05:15+00:00

Since commit 87c78b612f4f ("powerpc: Fix all occurences of "the the"")
fixed "the the", there's now a steady stream of patches fixing other
duplicate words.

Just fix them all at once, to save the overhead of dealing with
individual patches for each case.

This leaves a few cases of "that that", which in some contexts is
correct.

Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220718095158.326606-1-mpe@ellerman.id.au

powerpc: Don't include asm/setup.h in asm/machdep.h

2022-06-20T01:29:49+00:00

asm/machdep.h doesn't need asm/setup.h

Remove it.

Add it directly in files that needs it.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/3b1dfb19a2c3265fb4abc2bfc7b6eae9261a998b.1654966508.git.christophe.leroy@csgroup.eu

powerpc: Fix all occurences of "the the"

2022-05-22T05:59:43+00:00

Rather than waiting for the bots to fix these one-by-one, fix all
occurences of "the the" throughout arch/powerpc.

Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220518142629.513007-1-mpe@ellerman.id.au