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-rw-r--r--arch/sh/drivers/pci/ops-sh4.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/sh/drivers/pci/ops-sh4.c b/arch/sh/drivers/pci/ops-sh4.c
new file mode 100644
index 0000000000..a205be3bfc
--- /dev/null
+++ b/arch/sh/drivers/pci/ops-sh4.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic SH-4 / SH-4A PCIC operations (SH7751, SH7780).
+ *
+ * Copyright (C) 2002 - 2009 Paul Mundt
+ */
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <asm/addrspace.h>
+#include "pci-sh4.h"
+
+/*
+ * Direct access to PCI hardware...
+ */
+#define CONFIG_CMD(bus, devfn, where) \
+ (0x80000000 | (bus->number << 16) | (devfn << 8) | (where & ~3))
+
+/*
+ * Functions for accessing PCI configuration space with type 1 accesses
+ */
+static int sh4_pci_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val)
+{
+ struct pci_channel *chan = bus->sysdata;
+ unsigned long flags;
+ u32 data;
+
+ /*
+ * PCIPDR may only be accessed as 32 bit words,
+ * so we must do byte alignment by hand
+ */
+ raw_spin_lock_irqsave(&pci_config_lock, flags);
+ pci_write_reg(chan, CONFIG_CMD(bus, devfn, where), SH4_PCIPAR);
+ data = pci_read_reg(chan, SH4_PCIPDR);
+ raw_spin_unlock_irqrestore(&pci_config_lock, flags);
+
+ switch (size) {
+ case 1:
+ *val = (data >> ((where & 3) << 3)) & 0xff;
+ break;
+ case 2:
+ *val = (data >> ((where & 2) << 3)) & 0xffff;
+ break;
+ case 4:
+ *val = data;
+ break;
+ default:
+ return PCIBIOS_FUNC_NOT_SUPPORTED;
+ }
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+/*
+ * Since SH4 only does 32bit access we'll have to do a read,
+ * mask,write operation.
+ * We'll allow an odd byte offset, though it should be illegal.
+ */
+static int sh4_pci_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val)
+{
+ struct pci_channel *chan = bus->sysdata;
+ unsigned long flags;
+ int shift;
+ u32 data;
+
+ raw_spin_lock_irqsave(&pci_config_lock, flags);
+ pci_write_reg(chan, CONFIG_CMD(bus, devfn, where), SH4_PCIPAR);
+ data = pci_read_reg(chan, SH4_PCIPDR);
+ raw_spin_unlock_irqrestore(&pci_config_lock, flags);
+
+ switch (size) {
+ case 1:
+ shift = (where & 3) << 3;
+ data &= ~(0xff << shift);
+ data |= ((val & 0xff) << shift);
+ break;
+ case 2:
+ shift = (where & 2) << 3;
+ data &= ~(0xffff << shift);
+ data |= ((val & 0xffff) << shift);
+ break;
+ case 4:
+ data = val;
+ break;
+ default:
+ return PCIBIOS_FUNC_NOT_SUPPORTED;
+ }
+
+ pci_write_reg(chan, data, SH4_PCIPDR);
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops sh4_pci_ops = {
+ .read = sh4_pci_read,
+ .write = sh4_pci_write,
+};
+
+int __attribute__((weak)) pci_fixup_pcic(struct pci_channel *chan)
+{
+ /* Nothing to do. */
+ return 0;
+}