Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1588752

[PATCH 06/20] PCI: ECAM: use pci_remap_cfgspace() to map config region

Show all headers | View raw

Current ECAM kernel implementation uses ioremap() to map the ECAM
configuration space memory region; this is not safe in that on some
architectures the ioremap interface provides mappings that allow posted
write transactions. This, as highlighted in the PCIe specifications
(4.0 - Rev0.3, "Ordering Considerations for the Enhanced Configuration
Address Mechanism"), can create ordering issues for software because
posted writes transactions on the CPU host bus are non posted in the
PCI express fabric.

Update the ioremap() interface to use pci_remap_cfgspace() whose
mapping attributes guarantee that non-posted writes transactions
are issued for memory writes within the ECAM memory mapped address
region.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/ecam.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/ecam.c b/drivers/pci/ecam.c
index 2fee61b..e2068a4 100644
--- a/drivers/pci/ecam.c
+++ b/drivers/pci/ecam.c
@@ -84,12 +84,13 @@ struct pci_config_window *pci_ecam_create(struct device *dev,
 		if (!cfg->winp)
 			goto err_exit_malloc;
 		for (i = 0; i < bus_range; i++) {
-			cfg->winp[i] = ioremap(cfgres->start + i * bsz, bsz);
+			cfg->winp[i] =
+				pci_remap_cfgspace(cfgres->start + i * bsz, bsz);
 			if (!cfg->winp[i])
 				goto err_exit_iomap;
 		}
 	} else {
-		cfg->win = ioremap(cfgres->start, bus_range * bsz);
+		cfg->win = pci_remap_cfgspace(cfgres->start, bus_range * bsz);
 		if (!cfg->win)
 			goto err_exit_iomap;
 	}
-- 
2.10.0

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 00/20] PCI: fix config and I/O Address space memory mappings Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:20 +0100
  [PATCH 17/20] PCI: xgene: update PCI config space remap function Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:20 +0100
  [PATCH 03/20] asm-generic/io.h: add PCI config space remap interface Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:20 +0100
  [PATCH 15/20] PCI: designware: update PCI config space remap function Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:20 +0100
  [PATCH 04/20] ARM64: implement pci_remap_cfgspace() interface Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:20 +0100
  [PATCH 14/20] PCI: hisi: update PCI config space remap function Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:20 +0100
  [PATCH 01/20] PCI: remove __weak tag from pci_remap_iospace() Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:30 +0100
  [PATCH 05/20] ARM: implement pci_remap_cfgspace() interface Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:30 +0100
  [PATCH 08/20] PCI: xilinx: update PCI config space remap function Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:30 +0100
  [PATCH 10/20] PCI: spear13xx: update PCI config space remap function Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:30 +0100
  [PATCH 06/20] PCI: ECAM: use pci_remap_cfgspace() to map config region Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:30 +0100
  [PATCH 07/20] PCI: implement Devres interface to map PCI config space Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:30 +0100
    Re: [PATCH 07/20] PCI: implement Devres interface to map PCI config  space Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-28 11:50 +0100
  [PATCH 09/20] PCI: xilinx-nwl: update PCI config space remap function Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-02-27 16:30 +0100

csiph-web