1 files changed, 294 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pasemi/pci.c b/arch/powerpc/platforms/pasemi/pci.c
new file mode 100644
index 000000000..f27d31414
--- /dev/null
+++ b/arch/powerpc/platforms/pasemi/pci.c
@@ -0,0 +1,294 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2006 PA Semi, Inc
+ *
+ * Authors: Kip Walker, PA Semi
+ *	    Olof Johansson, PA Semi
+ *
+ * Maintained by: Olof Johansson <olof@lixom.net>
+ *
+ * Based on arch/powerpc/platforms/maple/pci.c
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/pci.h>
+
+#include <asm/pci-bridge.h>
+#include <asm/isa-bridge.h>
+#include <asm/machdep.h>
+
+#include <asm/ppc-pci.h>
+
+#include "pasemi.h"
+
+#define PA_PXP_CFA(bus, devfn, off) (((bus) << 20) | ((devfn) << 12) | (off))
+
+static inline int pa_pxp_offset_valid(u8 bus, u8 devfn, int offset)
+{
+	/* Device 0 Function 0 is special: It's config space spans function 1 as
+	 * well, so allow larger offset. It's really a two-function device but the
+	 * second function does not probe.
+	 */
+	if (bus == 0 && devfn == 0)
+		return offset < 8192;
+	else
+		return offset < 4096;
+}
+
+static void volatile __iomem *pa_pxp_cfg_addr(struct pci_controller *hose,
+				       u8 bus, u8 devfn, int offset)
+{
+	return hose->cfg_data + PA_PXP_CFA(bus, devfn, offset);
+}
+
+static inline int is_root_port(int busno, int devfn)
+{
+	return ((busno == 0) && (PCI_FUNC(devfn) < 4) &&
+		 ((PCI_SLOT(devfn) == 16) || (PCI_SLOT(devfn) == 17)));
+}
+
+static inline int is_5945_reg(int reg)
+{
+	return (((reg >= 0x18) && (reg < 0x34)) ||
+		((reg >= 0x158) && (reg < 0x178)));
+}
+
+static int workaround_5945(struct pci_bus *bus, unsigned int devfn,
+			   int offset, int len, u32 *val)
+{
+	struct pci_controller *hose;
+	void volatile __iomem *addr, *dummy;
+	int byte;
+	u32 tmp;
+
+	if (!is_root_port(bus->number, devfn) || !is_5945_reg(offset))
+		return 0;
+
+	hose = pci_bus_to_host(bus);
+
+	addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset & ~0x3);
+	byte = offset & 0x3;
+
+	/* Workaround bug 5945: write 0 to a dummy register before reading,
+	 * and write back what we read. We must read/write the full 32-bit
+	 * contents so we need to shift and mask by hand.
+	 */
+	dummy = pa_pxp_cfg_addr(hose, bus->number, devfn, 0x10);
+	out_le32(dummy, 0);
+	tmp = in_le32(addr);
+	out_le32(addr, tmp);
+
+	switch (len) {
+	case 1:
+		*val = (tmp >> (8*byte)) & 0xff;
+		break;
+	case 2:
+		if (byte == 0)
+			*val = tmp & 0xffff;
+		else
+			*val = (tmp >> 16) & 0xffff;
+		break;
+	default:
+		*val = tmp;
+		break;
+	}
+
+	return 1;
+}
+
+#ifdef CONFIG_PPC_PASEMI_NEMO
+#define PXP_ERR_CFG_REG	0x4
+#define PXP_IGNORE_PCIE_ERRORS	0x800
+#define SB600_BUS 5
+
+static void sb600_set_flag(int bus)
+{
+	static void __iomem *iob_mapbase = NULL;
+	struct resource res;
+	struct device_node *dn;
+	int err;
+
+	if (iob_mapbase == NULL) {
+		dn = of_find_compatible_node(NULL, "isa", "pasemi,1682m-iob");
+		if (!dn) {
+			pr_crit("NEMO SB600 missing iob node\n");
+			return;
+		}
+
+		err = of_address_to_resource(dn, 0, &res);
+		of_node_put(dn);
+
+		if (err) {
+			pr_crit("NEMO SB600 missing resource\n");
+			return;
+		}
+
+		pr_info("NEMO SB600 IOB base %08llx\n",res.start);
+
+		iob_mapbase = ioremap(res.start + 0x100, 0x94);
+	}
+
+	if (iob_mapbase != NULL) {
+		if (bus == SB600_BUS) {
+			/*
+			 * This is the SB600's bus, tell the PCI-e root port
+			 * to allow non-zero devices to enumerate.
+			 */
+			out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) | PXP_IGNORE_PCIE_ERRORS);
+		} else {
+			/*
+			 * Only scan device 0 on other busses
+			 */
+			out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) & ~PXP_IGNORE_PCIE_ERRORS);
+		}
+	}
+}
+
+#else
+
+static void sb600_set_flag(int bus)
+{
+}
+#endif
+
+static int pa_pxp_read_config(struct pci_bus *bus, unsigned int devfn,
+			      int offset, int len, u32 *val)
+{
+	struct pci_controller *hose;
+	void volatile __iomem *addr;
+
+	hose = pci_bus_to_host(bus);
+	if (!hose)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	if (!pa_pxp_offset_valid(bus->number, devfn, offset))
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	if (workaround_5945(bus, devfn, offset, len, val))
+		return PCIBIOS_SUCCESSFUL;
+
+	addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset);
+
+	sb600_set_flag(bus->number);
+
+	/*
+	 * Note: the caller has already checked that offset is
+	 * suitably aligned and that len is 1, 2 or 4.
+	 */
+	switch (len) {
+	case 1:
+		*val = in_8(addr);
+		break;
+	case 2:
+		*val = in_le16(addr);
+		break;
+	default:
+		*val = in_le32(addr);
+		break;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int pa_pxp_write_config(struct pci_bus *bus, unsigned int devfn,
+			       int offset, int len, u32 val)
+{
+	struct pci_controller *hose;
+	void volatile __iomem *addr;
+
+	hose = pci_bus_to_host(bus);
+	if (!hose)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	if (!pa_pxp_offset_valid(bus->number, devfn, offset))
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset);
+
+	sb600_set_flag(bus->number);
+
+	/*
+	 * Note: the caller has already checked that offset is
+	 * suitably aligned and that len is 1, 2 or 4.
+	 */
+	switch (len) {
+	case 1:
+		out_8(addr, val);
+		break;
+	case 2:
+		out_le16(addr, val);
+		break;
+	default:
+		out_le32(addr, val);
+		break;
+	}
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops pa_pxp_ops = {
+	.read = pa_pxp_read_config,
+	.write = pa_pxp_write_config,
+};
+
+static void __init setup_pa_pxp(struct pci_controller *hose)
+{
+	hose->ops = &pa_pxp_ops;
+	hose->cfg_data = ioremap(0xe0000000, 0x10000000);
+}
+
+static int __init pas_add_bridge(struct device_node *dev)
+{
+	struct pci_controller *hose;
+
+	pr_debug("Adding PCI host bridge %pOF\n", dev);
+
+	hose = pcibios_alloc_controller(dev);
+	if (!hose)
+		return -ENOMEM;
+
+	hose->first_busno = 0;
+	hose->last_busno = 0xff;
+	hose->controller_ops = pasemi_pci_controller_ops;
+
+	setup_pa_pxp(hose);
+
+	pr_info("Found PA-PXP PCI host bridge.\n");
+
+	/* Interpret the "ranges" property */
+	pci_process_bridge_OF_ranges(hose, dev, 1);
+
+	/*
+	 * Scan for an isa bridge. This is needed to find the SB600 on the nemo
+	 * and does nothing on machines without one.
+	 */
+	isa_bridge_find_early(hose);
+
+	return 0;
+}
+
+void __init pas_pci_init(void)
+{
+	struct device_node *np;
+	int res;
+
+	pci_set_flags(PCI_SCAN_ALL_PCIE_DEVS);
+
+	np = of_find_compatible_node(of_root, NULL, "pasemi,rootbus");
+	if (np) {
+		res = pas_add_bridge(np);
+		of_node_put(np);
+	}
+}
+
+void __iomem *__init pasemi_pci_getcfgaddr(struct pci_dev *dev, int offset)
+{
+	struct pci_controller *hose;
+
+	hose = pci_bus_to_host(dev->bus);
+
+	return (void __iomem *)pa_pxp_cfg_addr(hose, dev->bus->number, dev->devfn, offset);
+}
+
+struct pci_controller_ops pasemi_pci_controller_ops;