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@@ -0,0 +1,126 @@
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+/*
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+ * linux/arch/arm/kernel/bios32.c
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+ *
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+ * PCI bios-type initialisation for PCI machines
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+ *
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+ * Bits taken from various places.
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+ */
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+#include <linux/export.h>
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+#include <linux/kernel.h>
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+#include <linux/pci.h>
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+#include <linux/slab.h>
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+#include <linux/init.h>
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+#include <linux/io.h>
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+
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+#include <asm/mach-types.h>
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+#include <asm/mach/map.h>
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+#include <asm/mach/pci.h>
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+
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+static int debug_pci;
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+
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+/*
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+ * We can't use pci_find_device() here since we are
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+ * called from interrupt context.
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+ */
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+static void pcibios_bus_report_status(struct pci_bus *bus, u_int status_mask, int warn)
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+{
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+ struct pci_dev *dev;
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+
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+ list_for_each_entry(dev, &bus->devices, bus_list) {
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+ u16 status;
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+
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+ /*
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+ * ignore host bridge - we handle
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+ * that separately
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+ */
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+ if (dev->bus->number == 0 && dev->devfn == 0)
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+ continue;
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+
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+ pci_read_config_word(dev, PCI_STATUS, &status);
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+ if (status == 0xffff)
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+ continue;
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+
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+ if ((status & status_mask) == 0)
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+ continue;
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+
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+ /* clear the status errors */
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+ pci_write_config_word(dev, PCI_STATUS, status & status_mask);
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+
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+ if (warn)
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+ printk("(%s: %04X) ", pci_name(dev), status);
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+ }
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+
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+ list_for_each_entry(dev, &bus->devices, bus_list)
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+ if (dev->subordinate)
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+ pcibios_bus_report_status(dev->subordinate, status_mask, warn);
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+}
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+
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+void pcibios_report_status(u_int status_mask, int warn)
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+{
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+ struct list_head *l;
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+
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+ list_for_each(l, &pci_root_buses) {
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+ struct pci_bus *bus = pci_bus_b(l);
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+
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+ pcibios_bus_report_status(bus, status_mask, warn);
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+ }
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+}
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+
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+/*
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+ * We don't use this to fix the device, but initialisation of it.
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+ * It's not the correct use for this, but it works.
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+ * Note that the arbiter/ISA bridge appears to be buggy, specifically in
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+ * the following area:
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+ * 1. park on CPU
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+ * 2. ISA bridge ping-pong
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+ * 3. ISA bridge master handling of target RETRY
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+ *
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+ * Bug 3 is responsible for the sound DMA grinding to a halt. We now
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+ * live with bug 2.
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+ */
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+static void pci_fixup_83c553(struct pci_dev *dev)
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+{
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+ /*
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+ * Set memory region to start at address 0, and enable IO
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+ */
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+ pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, PCI_BASE_ADDRESS_SPACE_MEMORY);
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+ pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_IO);
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+
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+ dev->resource[0].end -= dev->resource[0].start;
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+ dev->resource[0].start = 0;
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+
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+ /*
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+ * All memory requests from ISA to be channelled to PCI
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+ */
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+ pci_write_config_byte(dev, 0x48, 0xff);
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+
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+ /*
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+ * Enable ping-pong on bus master to ISA bridge transactions.
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+ * This improves the sound DMA substantially. The fixed
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+ * priority arbiter also helps (see below).
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+ */
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+ pci_write_config_byte(dev, 0x42, 0x01);
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+
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+ /*
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+ * Enable PCI retry
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+ */
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+ pci_write_config_byte(dev, 0x40, 0x22);
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+
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+ /*
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+ * We used to set the arbiter to "park on last master" (bit
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+ * 1 set), but unfortunately the CyberPro does not park the
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+ * bus. We must therefore park on CPU. Unfortunately, this
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+ * may trigger yet another bug in the 553.
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+ */
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+ pci_write_config_byte(dev, 0x83, 0x02);
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+
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+ /*
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+ * Make the ISA DMA request lowest priority, and disable
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+ * rotating priorities completely.
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+ */
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+ pci_write_config_byte(dev, 0x80, 0x11);
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+ pci_write_config_byte(dev, 0x81, 0x00);
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+
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+ /*
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+ * Route INTA input to IRQ 11, and set IRQ11 to be level
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+ * sensitive.
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