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-rw-r--r--arch/sh/drivers/pci/Makefile1
-rw-r--r--arch/sh/drivers/pci/fixups-sdk7786.c68
-rw-r--r--arch/sh/drivers/pci/pci.c2
3 files changed, 70 insertions, 1 deletions
diff --git a/arch/sh/drivers/pci/Makefile b/arch/sh/drivers/pci/Makefile
index 4a59e68..82f0a33 100644
--- a/arch/sh/drivers/pci/Makefile
+++ b/arch/sh/drivers/pci/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_SH_RTS7751R2D) += fixups-rts7751r2d.o
obj-$(CONFIG_SH_SH03) += fixups-sh03.o
obj-$(CONFIG_SH_HIGHLANDER) += fixups-r7780rp.o
obj-$(CONFIG_SH_SH7785LCR) += fixups-r7780rp.o
+obj-$(CONFIG_SH_SDK7786) += fixups-sdk7786.o
obj-$(CONFIG_SH_SDK7780) += fixups-sdk7780.o
obj-$(CONFIG_SH_7780_SOLUTION_ENGINE) += fixups-sdk7780.o
obj-$(CONFIG_SH_TITAN) += fixups-titan.o
diff --git a/arch/sh/drivers/pci/fixups-sdk7786.c b/arch/sh/drivers/pci/fixups-sdk7786.c
new file mode 100644
index 0000000..058a65a
--- /dev/null
+++ b/arch/sh/drivers/pci/fixups-sdk7786.c
@@ -0,0 +1,68 @@
+/*
+ * SDK7786 FPGA PCIe mux handling
+ *
+ * Copyright (C) 2010 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#define pr_fmt(fmt) "PCI: " fmt
+
+#include <linux/init.h>
+#include <linux/clk.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <mach/fpga.h>
+
+/*
+ * The SDK7786 FPGA supports mangling of most of the slots in some way or
+ * another. Slots 3/4 are special in that only one can be supported at a
+ * time, and both appear on port 3 to the PCI bus scan. Enabling slot 4
+ * (the horizontal edge connector) will disable slot 3 entirely.
+ *
+ * Misconfigurations can be detected through the FPGA via the slot
+ * resistors to determine card presence. Hotplug remains unsupported.
+ */
+static unsigned int slot4en __devinitdata;
+
+char *__devinit pcibios_setup(char *str)
+{
+ if (strcmp(str, "slot4en") == 0) {
+ slot4en = 1;
+ return NULL;
+ }
+
+ return str;
+}
+
+static int __init sdk7786_pci_init(void)
+{
+ u16 data = fpga_read_reg(PCIECR);
+
+ /*
+ * Enable slot #4 if it's been specified on the command line.
+ *
+ * Optionally reroute if slot #4 has a card present while slot #3
+ * does not, regardless of command line value.
+ *
+ * Card presence is logically inverted.
+ */
+ slot4en ?: (!(data & PCIECR_PRST4) && (data & PCIECR_PRST3));
+ if (slot4en) {
+ pr_info("Activating PCIe slot#4 (disabling slot#3)\n");
+
+ data &= ~PCIECR_PCIEMUX1;
+ fpga_write_reg(data, PCIECR);
+
+ /* Warn about forced rerouting if slot#3 is occupied */
+ if ((data & PCIECR_PRST3) == 0) {
+ pr_warning("Unreachable card detected in slot#3\n");
+ return -EBUSY;
+ }
+ } else
+ pr_info("PCIe slot#4 disabled\n");
+
+ return 0;
+}
+postcore_initcall(sdk7786_pci_init);
diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
index af4191b..60ee09a 100644
--- a/arch/sh/drivers/pci/pci.c
+++ b/arch/sh/drivers/pci/pci.c
@@ -268,7 +268,7 @@ void __init pcibios_update_irq(struct pci_dev *dev, int irq)
pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
}
-char * __devinit pcibios_setup(char *str)
+char * __devinit __weak pcibios_setup(char *str)
{
return str;
}
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