3.2.70-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Alexander Sverdlin <[email protected]>

commit 73bf3c2a500b2db8ac966469591196bf55afb409 upstream.

udelay() in PCI/PCIe read/write callbacks cause 30ms IRQ latency on Octeon
platforms because these operations are called from PCI_OP_READ() and
PCI_OP_WRITE() under raw_spin_lock_irqsave().

Signed-off-by: Alexander Sverdlin <[email protected]>
Cc: [email protected]
Cc: David Daney <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Jiri Kosina <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Masanari Iida <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Mathias <[email protected]>
Patchwork: https://patchwork.linux-mips.org/patch/9576/
Signed-off-by: Ralf Baechle <[email protected]>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <[email protected]>
---
 arch/mips/include/asm/octeon/pci-octeon.h | 3 ---
 arch/mips/pci/pci-octeon.c                | 6 ------
 arch/mips/pci/pcie-octeon.c               | 8 --------
 3 files changed, 17 deletions(-)

--- a/arch/mips/include/asm/octeon/pci-octeon.h
+++ b/arch/mips/include/asm/octeon/pci-octeon.h
@@ -11,9 +11,6 @@
 
 #include <linux/pci.h>
 
-/* Some PCI cards require delays when accessing config space. */
-#define PCI_CONFIG_SPACE_DELAY 10000
-
 /*
  * The physical memory base mapped by BAR1.  256MB at the end of the
  * first 4GB.
--- a/arch/mips/pci/pci-octeon.c
+++ b/arch/mips/pci/pci-octeon.c
@@ -279,9 +279,6 @@ static int octeon_read_config(struct pci
        pci_addr.s.func = devfn & 0x7;
        pci_addr.s.reg = reg;
 
-#if PCI_CONFIG_SPACE_DELAY
-       udelay(PCI_CONFIG_SPACE_DELAY);
-#endif
        switch (size) {
        case 4:
                *val = le32_to_cpu(cvmx_read64_uint32(pci_addr.u64));
@@ -316,9 +313,6 @@ static int octeon_write_config(struct pc
        pci_addr.s.func = devfn & 0x7;
        pci_addr.s.reg = reg;
 
-#if PCI_CONFIG_SPACE_DELAY
-       udelay(PCI_CONFIG_SPACE_DELAY);
-#endif
        switch (size) {
        case 4:
                cvmx_write64_uint32(pci_addr.u64, cpu_to_le32(val));
--- a/arch/mips/pci/pcie-octeon.c
+++ b/arch/mips/pci/pcie-octeon.c
@@ -1219,9 +1219,6 @@ static inline int octeon_pcie_write_conf
                                        devfn & 0x7, reg, val);
                return PCIBIOS_SUCCESSFUL;
        }
-#if PCI_CONFIG_SPACE_DELAY
-       udelay(PCI_CONFIG_SPACE_DELAY);
-#endif
        return PCIBIOS_FUNC_NOT_SUPPORTED;
 }
 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to