lkml.org 
[lkml]   [2006]   [Dec]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 3/6] PCI Express get/set read request size
Add PCI infrastructure for setting read request size.
The pcie_get_readrq is commented out because there are no drivers
that need it.


---
drivers/pci/pci.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++-
include/linux/pci.h | 4 ++-
2 files changed, 67 insertions(+), 2 deletions(-)
--- pci-x.orig/drivers/pci/pci.c
+++ pci-x/drivers/pci/pci.c
@@ -1139,7 +1139,70 @@ out:
}
EXPORT_SYMBOL(pcix_set_mmrbc);

-
+#if 0
+/**
+ * pcie_get_readrq - get PCI Express read request size
+ * @dev: PCI device to query
+ *
+ * Returns maximum memory read request in bytes
+ * or appropriate error value.
+ */
+int pcie_get_readrq(struct pci_dev *dev)
+{
+ int ret, cap;
+ u16 ctl;
+
+ cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
+ if (!cap)
+ return -EINVAL;
+
+ ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
+ if (!ret)
+ ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
+
+ return ret;
+}
+EXPORT_SYMBOL(pcie_get_readrq);
+#endif
+
+/**
+ * pcie_set_readrq - set PCI Express maximum memory read request
+ * @dev: PCI device to query
+ * @count: maximum memory read count in bytes
+ * valid values are 128, 256, 512, 1024, 2048, 4096
+ *
+ * If possible sets maximum read byte count
+ */
+int
+pcie_set_readrq(struct pci_dev *dev, int count)
+{
+ int cap, err = -EINVAL;
+ u16 ctl, v;
+
+ if (count < 128 || count > 4096 || (count & (count-1)))
+ goto out;
+
+ v = (ffs(count) - 8) << 12;
+
+ cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
+ if (!cap)
+ goto out;
+
+ err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
+ if (err)
+ goto out;
+
+ if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
+ ctl &= ~PCI_EXP_DEVCTL_READRQ;
+ ctl |= v;
+ err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
+ }
+
+out:
+ return err;
+}
+EXPORT_SYMBOL(pcie_set_readrq);
+
static int __devinit pci_init(void)
{
struct pci_dev *dev = NULL;
--- pci-x.orig/include/linux/pci.h
+++ pci-x/include/linux/pci.h
@@ -513,7 +513,9 @@ void pci_intx(struct pci_dev *dev, int e
int pci_set_dma_mask(struct pci_dev *dev, u64 mask);
int pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask);
int pcix_get_mmrbc(struct pci_dev *dev);
-int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc);
+int pcix_set_mmrbc(struct pci_dev *dev, int rq);
+int pcie_get_readrq(struct pci_dev *dev);
+int pcie_set_readrq(struct pci_dev *dev, int rq);
void pci_update_resource(struct pci_dev *dev, struct resource *res, int resno);
int __must_check pci_assign_resource(struct pci_dev *dev, int i);
int __must_check pci_assign_resource_fixed(struct pci_dev *dev, int i);
--

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

\
 
 \ /
  Last update: 2006-12-08 19:33    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site