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linux/drivers/parisc
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Bjorn Helgaas 237865f195 PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code" 
Revert dff22d2054 ("PCI: Call pci_read_bridge_bases() from core instead
of arch code").

Reading PCI bridge windows is not arch-specific in itself, but there is PCI
core code that doesn't work correctly if we read them too early.  For
example, Hannes found this case on an ARM Freescale i.mx6 board:

  pci_bus 0000:00: root bus resource [mem 0x01000000-0x01efffff]
  pci 0000:00:00.0: PCI bridge to [bus 01-ff]
  pci 0000:00:00.0: BAR 8: no space for [mem size 0x01000000] (mem window)
  pci 0000:01:00.0: BAR 2: failed to assign [mem size 0x00200000]
  pci 0000:01:00.0: BAR 1: failed to assign [mem size 0x00004000]
  pci 0000:01:00.0: BAR 0: failed to assign [mem size 0x00000100]

The 00:00.0 mem window needs to be at least 3MB: the 01:00.0 device needs
0x204100 of space, and mem windows are megabyte-aligned.

Bus sizing can increase a bridge window size, but never *decrease* it (see
d65245c329 ("PCI: don't shrink bridge resources")).  Prior to
dff22d2054, ARM didn't read bridge windows at all, so the "original size"
was zero, and we assigned a 3MB window.

After dff22d2054, we read the bridge windows before sizing the bus.  The
firmware programmed a 16MB window (size 0x01000000) in 00:00.0, and since
we never decrease the size, we kept 16MB even though we only needed 3MB.
But 16MB doesn't fit in the host bridge aperture, so we failed to assign
space for the window and the downstream devices.

I think this is a defect in the PCI core: we shouldn't rely on the firmware
to assign sensible windows.

Ray reported a similar problem, also on ARM, with Broadcom iProc.

Issues like this are too hard to fix right now, so revert dff22d2054.

Reported-by: Hannes <oe5hpm@gmail.com>
Reported-by: Ray Jui <rjui@broadcom.com>
Link: http://lkml.kernel.org/r/CAAa04yFQEUJm7Jj1qMT57-LG7ZGtnhNDBe=PpSRa70Mj+XhW-A@mail.gmail.com
Link: http://lkml.kernel.org/r/55F75BB8.4070405@broadcom.com
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2015-09-15 13:18:04 -05:00
..
asp.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
ccio-dma.c parisc: use seq_hex_dump() to dump buffers 2015-09-10 13:29:01 -07:00
ccio-rm-dma.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
dino.c PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code" 2015-09-15 13:18:04 -05:00
eisa_eeprom.c eisa_eeprom: switch to fixed_size_llseek() 2013-06-29 12:57:29 +04:00
eisa_enumerator.c treewide: Fix typo in printk messages 2015-03-06 23:05:39 +01:00
eisa.c parisc: Convert irq namespace 2011-03-29 14:48:08 +02:00
gsc.c parisc: Convert irq namespace 2011-03-29 14:48:08 +02:00
gsc.h parisc: remove obsolete hw_interrupt_type 2009-07-03 03:34:08 +00:00
hppb.c drivers/parisc: Use printf extension %pR for struct resource 2013-02-20 22:47:24 +01:00
iommu-helpers.h parisc: Eliminate sg_virt_addr() and private scatterlist.h 2015-04-21 22:02:43 +02:00
iosapic_private.h
iosapic.c parisc/irq: Use access helper irq_data_get_affinity_mask() 2015-07-31 22:20:04 +02:00
Kconfig parisc: led driver requires CONFIG_VM_EVENT_COUNTERS 2013-02-20 22:51:52 +01:00
lasi.c
lba_pci.c PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code" 2015-09-15 13:18:04 -05:00
led.c procfs: new helper - PDE_DATA(inode) 2013-04-09 14:13:32 -04:00
Makefile
pdc_stable.c parisc: pdc_stable.c: Avoid potential stack overflows 2014-09-21 22:31:08 +02:00
power.c sched, cleanup, treewide: Remove set_current_state(TASK_RUNNING) after schedule() 2014-09-19 12:35:17 +02:00
README.dino Update broken web addresses in the kernel. 2010-10-18 11:03:14 +02:00
sba_iommu.c parisc: use seq_hex_dump() to dump buffers 2015-09-10 13:29:01 -07:00
superio.c parisc: %pf is only for function pointers 2015-04-24 13:45:54 +02:00
wax.c

README.dino 

/*
** HP VISUALIZE Workstation PCI Bus Defect
**
** "HP has discovered a potential system defect that can affect
** the behavior of five models of HP VISUALIZE workstations when
** equipped with third-party or customer-installed PCI I/O expansion
** cards. The defect is limited to the HP C180, C160, C160L, B160L,
** and B132L VISUALIZE workstations, and will only be encountered
** when data is transmitted through PCI I/O expansion cards on the
** PCI bus. HP-supplied graphics cards that utilize the PCI bus are
** not affected."
**
** http://h20000.www2.hp.com/bizsupport/TechSupport/Home.jsp?locale=en_US&prodTypeId=12454&prodSeriesId=44443
**
**	Product		First Good Serial Number
**  C200/C240 (US)	US67350000
**B132L+/B180 (US)	US67390000
**   C200 (Europe)	3713G01000
**  B180L (Europe)	3720G01000
**
** Note that many boards were fixed/replaced under a free replacement
** program. Assume a machine is only "suspect" until proven otherwise.
**
** "The pci_check program will also be available as application
**  patch PHSS_12295"
*/