1 files changed, 451 insertions, 0 deletions
diff --git a/arch/arm/mach-ixp4xx/common-pci.c b/arch/arm/mach-ixp4xx/common-pci.c
new file mode 100644
index 000000000..893c19c25
--- /dev/null
+++ b/arch/arm/mach-ixp4xx/common-pci.c
@@ -0,0 +1,451 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch/arm/mach-ixp4xx/common-pci.c 
+ *
+ * IXP4XX PCI routines for all platforms
+ *
+ * Maintainer: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * Copyright (C) 2002 Intel Corporation.
+ * Copyright (C) 2003 Greg Ungerer <gerg@snapgear.com>
+ * Copyright (C) 2003-2004 MontaVista Software, Inc.
+ */
+
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/export.h>
+#include <asm/dma-mapping.h>
+
+#include <asm/cputype.h>
+#include <asm/irq.h>
+#include <linux/sizes.h>
+#include <asm/mach/pci.h>
+#include <mach/hardware.h>
+
+
+/*
+ * IXP4xx PCI read function is dependent on whether we are 
+ * running A0 or B0 (AppleGate) silicon.
+ */
+int (*ixp4xx_pci_read)(u32 addr, u32 cmd, u32* data);
+
+/*
+ * Base address for PCI register region
+ */
+unsigned long ixp4xx_pci_reg_base = 0;
+
+/*
+ * PCI cfg an I/O routines are done by programming a 
+ * command/byte enable register, and then read/writing
+ * the data from a data register. We need to ensure
+ * these transactions are atomic or we will end up
+ * with corrupt data on the bus or in a driver.
+ */
+static DEFINE_RAW_SPINLOCK(ixp4xx_pci_lock);
+
+/*
+ * Read from PCI config space
+ */
+static void crp_read(u32 ad_cbe, u32 *data)
+{
+	unsigned long flags;
+	raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
+	*PCI_CRP_AD_CBE = ad_cbe;
+	*data = *PCI_CRP_RDATA;
+	raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
+}
+
+/*
+ * Write to PCI config space
+ */
+static void crp_write(u32 ad_cbe, u32 data)
+{ 
+	unsigned long flags;
+	raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
+	*PCI_CRP_AD_CBE = CRP_AD_CBE_WRITE | ad_cbe;
+	*PCI_CRP_WDATA = data;
+	raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
+}
+
+static inline int check_master_abort(void)
+{
+	/* check Master Abort bit after access */
+	unsigned long isr = *PCI_ISR;
+
+	if (isr & PCI_ISR_PFE) {
+		/* make sure the Master Abort bit is reset */    
+		*PCI_ISR = PCI_ISR_PFE;
+		pr_debug("%s failed\n", __func__);
+		return 1;
+	}
+
+	return 0;
+}
+
+int ixp4xx_pci_read_errata(u32 addr, u32 cmd, u32* data)
+{
+	unsigned long flags;
+	int retval = 0;
+	int i;
+
+	raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
+
+	*PCI_NP_AD = addr;
+
+	/* 
+	 * PCI workaround  - only works if NP PCI space reads have 
+	 * no side effects!!! Read 8 times. last one will be good.
+	 */
+	for (i = 0; i < 8; i++) {
+		*PCI_NP_CBE = cmd;
+		*data = *PCI_NP_RDATA;
+		*data = *PCI_NP_RDATA;
+	}
+
+	if(check_master_abort())
+		retval = 1;
+
+	raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
+	return retval;
+}
+
+int ixp4xx_pci_read_no_errata(u32 addr, u32 cmd, u32* data)
+{
+	unsigned long flags;
+	int retval = 0;
+
+	raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
+
+	*PCI_NP_AD = addr;
+
+	/* set up and execute the read */    
+	*PCI_NP_CBE = cmd;
+
+	/* the result of the read is now in NP_RDATA */
+	*data = *PCI_NP_RDATA; 
+
+	if(check_master_abort())
+		retval = 1;
+
+	raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
+	return retval;
+}
+
+int ixp4xx_pci_write(u32 addr, u32 cmd, u32 data)
+{    
+	unsigned long flags;
+	int retval = 0;
+
+	raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
+
+	*PCI_NP_AD = addr;
+
+	/* set up the write */
+	*PCI_NP_CBE = cmd;
+
+	/* execute the write by writing to NP_WDATA */
+	*PCI_NP_WDATA = data;
+
+	if(check_master_abort())
+		retval = 1;
+
+	raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
+	return retval;
+}
+
+static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where)
+{
+	u32 addr;
+	if (!bus_num) {
+		/* type 0 */
+		addr = BIT(32-PCI_SLOT(devfn)) | ((PCI_FUNC(devfn)) << 8) | 
+		    (where & ~3);	
+	} else {
+		/* type 1 */
+		addr = (bus_num << 16) | ((PCI_SLOT(devfn)) << 11) | 
+			((PCI_FUNC(devfn)) << 8) | (where & ~3) | 1;
+	}
+	return addr;
+}
+
+/*
+ * Mask table, bits to mask for quantity of size 1, 2 or 4 bytes.
+ * 0 and 3 are not valid indexes...
+ */
+static u32 bytemask[] = {
+	/*0*/	0,
+	/*1*/	0xff,
+	/*2*/	0xffff,
+	/*3*/	0,
+	/*4*/	0xffffffff,
+};
+
+static u32 local_byte_lane_enable_bits(u32 n, int size)
+{
+	if (size == 1)
+		return (0xf & ~BIT(n)) << CRP_AD_CBE_BESL;
+	if (size == 2)
+		return (0xf & ~(BIT(n) | BIT(n+1))) << CRP_AD_CBE_BESL;
+	if (size == 4)
+		return 0;
+	return 0xffffffff;
+}
+
+static int local_read_config(int where, int size, u32 *value)
+{ 
+	u32 n, data;
+	pr_debug("local_read_config from %d size %d\n", where, size);
+	n = where % 4;
+	crp_read(where & ~3, &data);
+	*value = (data >> (8*n)) & bytemask[size];
+	pr_debug("local_read_config read %#x\n", *value);
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int local_write_config(int where, int size, u32 value)
+{
+	u32 n, byte_enables, data;
+	pr_debug("local_write_config %#x to %d size %d\n", value, where, size);
+	n = where % 4;
+	byte_enables = local_byte_lane_enable_bits(n, size);
+	if (byte_enables == 0xffffffff)
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+	data = value << (8*n);
+	crp_write((where & ~3) | byte_enables, data);
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static u32 byte_lane_enable_bits(u32 n, int size)
+{
+	if (size == 1)
+		return (0xf & ~BIT(n)) << 4;
+	if (size == 2)
+		return (0xf & ~(BIT(n) | BIT(n+1))) << 4;
+	if (size == 4)
+		return 0;
+	return 0xffffffff;
+}
+
+static int ixp4xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
+{
+	u32 n, byte_enables, addr, data;
+	u8 bus_num = bus->number;
+
+	pr_debug("read_config from %d size %d dev %d:%d:%d\n", where, size,
+		bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
+
+	*value = 0xffffffff;
+	n = where % 4;
+	byte_enables = byte_lane_enable_bits(n, size);
+	if (byte_enables == 0xffffffff)
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	addr = ixp4xx_config_addr(bus_num, devfn, where);
+	if (ixp4xx_pci_read(addr, byte_enables | NP_CMD_CONFIGREAD, &data))
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	*value = (data >> (8*n)) & bytemask[size];
+	pr_debug("read_config_byte read %#x\n", *value);
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int ixp4xx_pci_write_config(struct pci_bus *bus,  unsigned int devfn, int where, int size, u32 value)
+{
+	u32 n, byte_enables, addr, data;
+	u8 bus_num = bus->number;
+
+	pr_debug("write_config_byte %#x to %d size %d dev %d:%d:%d\n", value, where,
+		size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
+
+	n = where % 4;
+	byte_enables = byte_lane_enable_bits(n, size);
+	if (byte_enables == 0xffffffff)
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	addr = ixp4xx_config_addr(bus_num, devfn, where);
+	data = value << (8*n);
+	if (ixp4xx_pci_write(addr, byte_enables | NP_CMD_CONFIGWRITE, data))
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops ixp4xx_ops = {
+	.read =  ixp4xx_pci_read_config,
+	.write = ixp4xx_pci_write_config,
+};
+
+/*
+ * PCI abort handler
+ */
+static int abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+{
+	u32 isr, status;
+
+	isr = *PCI_ISR;
+	local_read_config(PCI_STATUS, 2, &status);
+	pr_debug("PCI: abort_handler addr = %#lx, isr = %#x, "
+		"status = %#x\n", addr, isr, status);
+
+	/* make sure the Master Abort bit is reset */    
+	*PCI_ISR = PCI_ISR_PFE;
+	status |= PCI_STATUS_REC_MASTER_ABORT;
+	local_write_config(PCI_STATUS, 2, status);
+
+	/*
+	 * If it was an imprecise abort, then we need to correct the
+	 * return address to be _after_ the instruction.
+	 */
+	if (fsr & (1 << 10))
+		regs->ARM_pc += 4;
+
+	return 0;
+}
+
+void __init ixp4xx_pci_preinit(void)
+{
+	unsigned long cpuid = read_cpuid_id();
+
+#ifdef CONFIG_IXP4XX_INDIRECT_PCI
+	pcibios_min_mem = 0x10000000; /* 1 GB of indirect PCI MMIO space */
+#else
+	pcibios_min_mem = 0x48000000; /* 64 MB of PCI MMIO space */
+#endif
+	/*
+	 * Determine which PCI read method to use.
+	 * Rev 0 IXP425 requires workaround.
+	 */
+	if (!(cpuid & 0xf) && cpu_is_ixp42x()) {
+		printk("PCI: IXP42x A0 silicon detected - "
+			"PCI Non-Prefetch Workaround Enabled\n");
+		ixp4xx_pci_read = ixp4xx_pci_read_errata;
+	} else
+		ixp4xx_pci_read = ixp4xx_pci_read_no_errata;
+
+
+	/* hook in our fault handler for PCI errors */
+	hook_fault_code(16+6, abort_handler, SIGBUS, 0,
+			"imprecise external abort");
+
+	pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n");
+
+	/*
+	 * We use identity AHB->PCI address translation
+	 * in the 0x48000000 to 0x4bffffff address space
+	 */
+	*PCI_PCIMEMBASE = 0x48494A4B;
+
+	/*
+	 * We also use identity PCI->AHB address translation
+	 * in 4 16MB BARs that begin at the physical memory start
+	 */
+	*PCI_AHBMEMBASE = (PHYS_OFFSET & 0xFF000000) +
+		((PHYS_OFFSET & 0xFF000000) >> 8) +
+		((PHYS_OFFSET & 0xFF000000) >> 16) +
+		((PHYS_OFFSET & 0xFF000000) >> 24) +
+		0x00010203;
+
+	if (*PCI_CSR & PCI_CSR_HOST) {
+		printk("PCI: IXP4xx is host\n");
+
+		pr_debug("setup BARs in controller\n");
+
+		/*
+		 * We configure the PCI inbound memory windows to be
+		 * 1:1 mapped to SDRAM
+		 */
+		local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET);
+		local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + SZ_16M);
+		local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + SZ_32M);
+		local_write_config(PCI_BASE_ADDRESS_3, 4,
+					PHYS_OFFSET + SZ_32M + SZ_16M);
+
+		/*
+		 * Enable CSR window at 64 MiB to allow PCI masters
+		 * to continue prefetching past 64 MiB boundary.
+		 */
+		local_write_config(PCI_BASE_ADDRESS_4, 4, PHYS_OFFSET + SZ_64M);
+
+		/*
+		 * Enable the IO window to be way up high, at 0xfffffc00
+		 */
+		local_write_config(PCI_BASE_ADDRESS_5, 4, 0xfffffc01);
+		local_write_config(0x40, 4, 0x000080FF); /* No TRDY time limit */
+	} else {
+		printk("PCI: IXP4xx is target - No bus scan performed\n");
+	}
+
+	printk("PCI: IXP4xx Using %s access for memory space\n",
+#ifndef CONFIG_IXP4XX_INDIRECT_PCI
+			"direct"
+#else
+			"indirect"
+#endif
+		);
+
+	pr_debug("clear error bits in ISR\n");
+	*PCI_ISR = PCI_ISR_PSE | PCI_ISR_PFE | PCI_ISR_PPE | PCI_ISR_AHBE;
+
+	/*
+	 * Set Initialize Complete in PCI Control Register: allow IXP4XX to
+	 * respond to PCI configuration cycles. Specify that the AHB bus is
+	 * operating in big endian mode. Set up byte lane swapping between 
+	 * little-endian PCI and the big-endian AHB bus 
+	 */
+#ifdef __ARMEB__
+	*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE | PCI_CSR_PDS | PCI_CSR_ADS;
+#else
+	*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE;
+#endif
+
+	pr_debug("DONE\n");
+}
+
+int ixp4xx_setup(int nr, struct pci_sys_data *sys)
+{
+	struct resource *res;
+
+	if (nr >= 1)
+		return 0;
+
+	res = kcalloc(2, sizeof(*res), GFP_KERNEL);
+	if (res == NULL) {
+		/* 
+		 * If we're out of memory this early, something is wrong,
+		 * so we might as well catch it here.
+		 */
+		panic("PCI: unable to allocate resources?\n");
+	}
+
+	local_write_config(PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
+
+	res[0].name = "PCI I/O Space";
+	res[0].start = 0x00000000;
+	res[0].end = 0x0000ffff;
+	res[0].flags = IORESOURCE_IO;
+
+	res[1].name = "PCI Memory Space";
+	res[1].start = PCIBIOS_MIN_MEM;
+	res[1].end = PCIBIOS_MAX_MEM;
+	res[1].flags = IORESOURCE_MEM;
+
+	request_resource(&ioport_resource, &res[0]);
+	request_resource(&iomem_resource, &res[1]);
+
+	pci_add_resource_offset(&sys->resources, &res[0], sys->io_offset);
+	pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset);
+
+	return 1;
+}
+
+EXPORT_SYMBOL(ixp4xx_pci_read);
+EXPORT_SYMBOL(ixp4xx_pci_write);