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-rw-r--r--arch/mips/pci/ops-msc.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/arch/mips/pci/ops-msc.c b/arch/mips/pci/ops-msc.c
new file mode 100644
index 000000000..1f438baaf
--- /dev/null
+++ b/arch/mips/pci/ops-msc.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 1999, 2000, 2004, 2005 MIPS Technologies, Inc.
+ * All rights reserved.
+ * Authors: Carsten Langgaard <carstenl@mips.com>
+ * Maciej W. Rozycki <macro@mips.com>
+ * Copyright (C) 2005 Ralf Baechle (ralf@linux-mips.org)
+ *
+ * MIPS boards specific PCI support.
+ */
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+
+#include <asm/mips-boards/msc01_pci.h>
+
+#define PCI_ACCESS_READ 0
+#define PCI_ACCESS_WRITE 1
+
+/*
+ * PCI configuration cycle AD bus definition
+ */
+/* Type 0 */
+#define PCI_CFG_TYPE0_REG_SHF 0
+#define PCI_CFG_TYPE0_FUNC_SHF 8
+
+/* Type 1 */
+#define PCI_CFG_TYPE1_REG_SHF 0
+#define PCI_CFG_TYPE1_FUNC_SHF 8
+#define PCI_CFG_TYPE1_DEV_SHF 11
+#define PCI_CFG_TYPE1_BUS_SHF 16
+
+static int msc_pcibios_config_access(unsigned char access_type,
+ struct pci_bus *bus, unsigned int devfn, int where, u32 * data)
+{
+ unsigned char busnum = bus->number;
+ u32 intr;
+
+ /* Clear status register bits. */
+ MSC_WRITE(MSC01_PCI_INTSTAT,
+ (MSC01_PCI_INTCFG_MA_BIT | MSC01_PCI_INTCFG_TA_BIT));
+
+ MSC_WRITE(MSC01_PCI_CFGADDR,
+ ((busnum << MSC01_PCI_CFGADDR_BNUM_SHF) |
+ (PCI_SLOT(devfn) << MSC01_PCI_CFGADDR_DNUM_SHF) |
+ (PCI_FUNC(devfn) << MSC01_PCI_CFGADDR_FNUM_SHF) |
+ ((where / 4) << MSC01_PCI_CFGADDR_RNUM_SHF)));
+
+ /* Perform access */
+ if (access_type == PCI_ACCESS_WRITE)
+ MSC_WRITE(MSC01_PCI_CFGDATA, *data);
+ else
+ MSC_READ(MSC01_PCI_CFGDATA, *data);
+
+ /* Detect Master/Target abort */
+ MSC_READ(MSC01_PCI_INTSTAT, intr);
+ if (intr & (MSC01_PCI_INTCFG_MA_BIT | MSC01_PCI_INTCFG_TA_BIT)) {
+ /* Error occurred */
+
+ /* Clear bits */
+ MSC_WRITE(MSC01_PCI_INTSTAT,
+ (MSC01_PCI_INTCFG_MA_BIT | MSC01_PCI_INTCFG_TA_BIT));
+
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/*
+ * We can't address 8 and 16 bit words directly. Instead we have to
+ * read/write a 32bit word and mask/modify the data we actually want.
+ */
+static int msc_pcibios_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 * val)
+{
+ u32 data = 0;
+
+ if ((size == 2) && (where & 1))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+ else if ((size == 4) && (where & 3))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+
+ if (msc_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
+ &data))
+ return -1;
+
+ if (size == 1)
+ *val = (data >> ((where & 3) << 3)) & 0xff;
+ else if (size == 2)
+ *val = (data >> ((where & 3) << 3)) & 0xffff;
+ else
+ *val = data;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int msc_pcibios_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val)
+{
+ u32 data = 0;
+
+ if ((size == 2) && (where & 1))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+ else if ((size == 4) && (where & 3))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+
+ if (size == 4)
+ data = val;
+ else {
+ if (msc_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
+ where, &data))
+ return -1;
+
+ if (size == 1)
+ data = (data & ~(0xff << ((where & 3) << 3))) |
+ (val << ((where & 3) << 3));
+ else if (size == 2)
+ data = (data & ~(0xffff << ((where & 3) << 3))) |
+ (val << ((where & 3) << 3));
+ }
+
+ if (msc_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn, where,
+ &data))
+ return -1;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops msc_pci_ops = {
+ .read = msc_pcibios_read,
+ .write = msc_pcibios_write
+};