[ARM] 4601/1: KS8695: PCI support

This patch adds support for the PCI Host controller integrated in the
Kendin/Micrel KS8695 processor.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-ks8695/Makefile

@@ -9,7 +9,7 @@ obj-n				:=
 obj-				:=
 
 # PCI support is optional
-#obj-$(CONFIG_PCI)		+= pci.o
+obj-$(CONFIG_PCI)		+= pci.o
 
 # Board-specific support
 obj-$(CONFIG_MACH_KS8695)	+= board-micrel.o

arch/arm/mach-ks8695/board-micrel.c

@@ -40,7 +40,7 @@ static void __init micrel_init(void)
 	printk(KERN_INFO "Micrel KS8695 Development Board initializing\n");
 
 #ifdef CONFIG_PCI
-//	ks8695_init_pci(&micrel_pci);
+	ks8695_init_pci(&micrel_pci);
 #endif
 
 	/* Add devices */

arch/arm/mach-ks8695/pci.c

+/*
+ * arch/arm/mach-ks8695/pci.c
+ *
+ *  Copyright (C) 2003, Micrel Semiconductors
+ *  Copyright (C) 2006, Greg Ungerer <gerg@snapgear.com>
+ *  Copyright (C) 2006, Ben Dooks
+ *  Copyright (C) 2007, Andrew Victor
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+
+#include <asm/io.h>
+#include <asm/signal.h>
+#include <asm/mach/pci.h>
+#include <asm/hardware.h>
+
+#include <asm/arch/devices.h>
+#include <asm/arch/regs-pci.h>
+
+
+static int pci_dbg;
+static int pci_cfg_dbg;
+
+
+static void ks8695_pci_setupconfig(unsigned int bus_nr, unsigned int devfn, unsigned int where)
+{
+	unsigned long pbca;
+
+	pbca = PBCA_ENABLE | (where & ~3);
+	pbca |= PCI_SLOT(devfn) << 11 ;
+	pbca |= PCI_FUNC(devfn) << 8;
+	pbca |= bus_nr << 16;
+
+	if (bus_nr == 0) {
+		/* use Type-0 transaction */
+		__raw_writel(pbca, KS8695_PCI_VA + KS8695_PBCA);
+	} else {
+		/* use Type-1 transaction */
+		__raw_writel(pbca | PBCA_TYPE1, KS8695_PCI_VA + KS8695_PBCA);
+	}
+}
+
+
+/*
+ * The KS8695 datasheet prohibits anything other than 32bit accesses
+ * to the IO registers, so all our configuration must be done with
+ * 32bit operations, and the correct bit masking and shifting.
+ */
+
+static int ks8695_pci_readconfig(struct pci_bus *bus,
+			unsigned int devfn, int where, int size, u32 *value)
+{
+	ks8695_pci_setupconfig(bus->number, devfn, where);
+
+	*value = __raw_readl(KS8695_PCI_VA +  KS8695_PBCD);
+
+	switch (size) {
+		case 4:
+			break;
+		case 2:
+			*value = *value >> ((where & 2) * 8);
+			*value &= 0xffff;
+			break;
+		case 1:
+			*value = *value >> ((where & 3) * 8);
+			*value &= 0xff;
+			break;
+	}
+
+	if (pci_cfg_dbg) {
+		printk("read: %d,%08x,%02x,%d: %08x (%08x)\n",
+			bus->number, devfn, where, size, *value,
+			__raw_readl(KS8695_PCI_VA +  KS8695_PBCD));
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int ks8695_pci_writeconfig(struct pci_bus *bus,
+			unsigned int devfn, int where, int size, u32 value)
+{
+	unsigned long tmp;
+
+	if (pci_cfg_dbg) {
+		printk("write: %d,%08x,%02x,%d: %08x\n",
+			bus->number, devfn, where, size, value);
+	}
+
+	ks8695_pci_setupconfig(bus->number, devfn, where);
+
+	switch (size) {
+		case 4:
+			__raw_writel(value, KS8695_PCI_VA +  KS8695_PBCD);
+			break;
+		case 2:
+			tmp = __raw_readl(KS8695_PCI_VA +  KS8695_PBCD);
+			tmp &= ~(0xffff << ((where & 2) * 8));
+			tmp |= value << ((where & 2) * 8);
+
+			__raw_writel(tmp, KS8695_PCI_VA +  KS8695_PBCD);
+			break;
+		case 1:
+			tmp = __raw_readl(KS8695_PCI_VA +  KS8695_PBCD);
+			tmp &= ~(0xff << ((where & 3) * 8));
+			tmp |= value << ((where & 3) * 8);
+
+			__raw_writel(tmp, KS8695_PCI_VA +  KS8695_PBCD);
+			break;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static void ks8695_local_writeconfig(int where, u32 value)
+{
+	ks8695_pci_setupconfig(0, 0, where);
+	__raw_writel(value, KS8695_PCI_VA + KS8695_PBCD);
+}
+
+static struct pci_ops ks8695_pci_ops = {
+	.read	= ks8695_pci_readconfig,
+	.write	= ks8695_pci_writeconfig,
+};
+
+static struct pci_bus *ks8695_pci_scan_bus(int nr, struct pci_sys_data *sys)
+{
+	return pci_scan_bus(sys->busnr, &ks8695_pci_ops, sys);
+}
+
+static struct resource pci_mem = {
+	.name	= "PCI Memory space",
+	.start	= KS8695_PCIMEM_PA,
+	.end	= KS8695_PCIMEM_PA + (KS8695_PCIMEM_SIZE - 1),
+	.flags	= IORESOURCE_MEM,
+};
+
+static struct resource pci_io = {
+	.name	= "PCI IO space",
+	.start	= KS8695_PCIIO_PA,
+	.end	= KS8695_PCIIO_PA + (KS8695_PCIIO_SIZE - 1),
+	.flags	= IORESOURCE_IO,
+};
+
+static int __init ks8695_pci_setup(int nr, struct pci_sys_data *sys)
+{
+	if (nr > 0)
+		return 0;
+
+	request_resource(&iomem_resource, &pci_mem);
+	request_resource(&ioport_resource, &pci_io);
+
+	sys->resource[0] = &pci_io;
+	sys->resource[1] = &pci_mem;
+	sys->resource[2] = NULL;
+
+	/* Assign and enable processor bridge */
+	ks8695_local_writeconfig(PCI_BASE_ADDRESS_0, KS8695_PCIMEM_PA);
+
+	/* Enable bus-master & Memory Space access */
+	ks8695_local_writeconfig(PCI_COMMAND, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
+
+	/* Set cache-line size & latency. */
+	ks8695_local_writeconfig(PCI_CACHE_LINE_SIZE, (32 << 8) | (L1_CACHE_BYTES / sizeof(u32)));
+
+	/* Reserve PCI memory space for PCI-AHB resources */
+	if (!request_mem_region(KS8695_PCIMEM_PA, SZ_64M, "PCI-AHB Bridge")) {
+		printk(KERN_ERR "Cannot allocate PCI-AHB Bridge memory.\n");
+		return -EBUSY;
+	}
+
+	return 1;
+}
+
+static inline unsigned int size_mask(unsigned long size)
+{
+	return (~size) + 1;
+}
+
+static int ks8695_pci_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+{
+	unsigned long pc = instruction_pointer(regs);
+	unsigned long instr = *(unsigned long *)pc;
+	unsigned long cmdstat;
+
+	cmdstat = __raw_readl(KS8695_PCI_VA + KS8695_CRCFCS);
+
+	printk(KERN_ERR "PCI abort: address = 0x%08lx fsr = 0x%03x PC = 0x%08lx LR = 0x%08lx [%s%s%s%s%s]\n",
+		addr, fsr, regs->ARM_pc, regs->ARM_lr,
+		cmdstat & (PCI_STATUS_SIG_TARGET_ABORT << 16) ? "GenTarget" : " ",
+		cmdstat & (PCI_STATUS_REC_TARGET_ABORT << 16) ? "RecvTarget" : " ",
+		cmdstat & (PCI_STATUS_REC_MASTER_ABORT << 16) ? "MasterAbort" : " ",
+		cmdstat & (PCI_STATUS_SIG_SYSTEM_ERROR << 16) ? "SysError" : " ",
+		cmdstat & (PCI_STATUS_DETECTED_PARITY << 16)  ? "Parity" : " "
+	);
+
+	__raw_writel(cmdstat, KS8695_PCI_VA + KS8695_CRCFCS);
+
+	/*
+	 * If the instruction being executed was a read,
+	 * make it look like it read all-ones.
+	 */
+	if ((instr & 0x0c100000) == 0x04100000) {
+		int reg = (instr >> 12) & 15;
+		unsigned long val;
+
+		if (instr & 0x00400000)
+			val = 255;
+		else
+			val = -1;
+
+		regs->uregs[reg] = val;
+		regs->ARM_pc += 4;
+		return 0;
+	}
+
+	if ((instr & 0x0e100090) == 0x00100090) {
+		int reg = (instr >> 12) & 15;
+
+		regs->uregs[reg] = -1;
+		regs->ARM_pc += 4;
+		return 0;
+	}
+
+	return 1;
+}
+
+static void __init ks8695_pci_preinit(void)
+{
+	/* stage 1 initialization, subid, subdevice = 0x0001 */
+	__raw_writel(0x00010001, KS8695_PCI_VA + KS8695_CRCSID);
+
+	/* stage 2 initialization */
+	/* prefetch limits with 16 words, retry enable */
+	__raw_writel(0x40000000, KS8695_PCI_VA + KS8695_PBCS);
+
+	/* configure memory mapping */
+	__raw_writel(KS8695_PCIMEM_PA, KS8695_PCI_VA + KS8695_PMBA);
+	__raw_writel(size_mask(KS8695_PCIMEM_SIZE), KS8695_PCI_VA + KS8695_PMBAM);
+	__raw_writel(KS8695_PCIMEM_PA, KS8695_PCI_VA + KS8695_PMBAT);
+	__raw_writel(0, KS8695_PCI_VA + KS8695_PMBAC);
+
+	/* configure IO mapping */
+	__raw_writel(KS8695_PCIIO_PA, KS8695_PCI_VA + KS8695_PIOBA);
+	__raw_writel(size_mask(KS8695_PCIIO_SIZE), KS8695_PCI_VA + KS8695_PIOBAM);
+	__raw_writel(KS8695_PCIIO_PA, KS8695_PCI_VA + KS8695_PIOBAT);
+	__raw_writel(0, KS8695_PCI_VA + KS8695_PIOBAC);
+
+	/* hook in fault handlers */
+	hook_fault_code(8, ks8695_pci_fault, SIGBUS, "external abort on non-linefetch");
+	hook_fault_code(10, ks8695_pci_fault, SIGBUS, "external abort on non-linefetch");
+}
+
+static void ks8695_show_pciregs(void)
+{
+	if (!pci_dbg)
+		return;
+
+	printk(KERN_INFO "PCI: CRCFID = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_CRCFID));
+	printk(KERN_INFO "PCI: CRCFCS = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_CRCFCS));
+	printk(KERN_INFO "PCI: CRCFRV = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_CRCFRV));
+	printk(KERN_INFO "PCI: CRCFLT = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_CRCFLT));
+	printk(KERN_INFO "PCI: CRCBMA = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_CRCBMA));
+	printk(KERN_INFO "PCI: CRCSID = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_CRCSID));
+	printk(KERN_INFO "PCI: CRCFIT = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_CRCFIT));
+
+	printk(KERN_INFO "PCI: PBM    = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PBM));
+	printk(KERN_INFO "PCI: PBCS   = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PBCS));
+
+	printk(KERN_INFO "PCI: PMBA   = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PMBA));
+	printk(KERN_INFO "PCI: PMBAC  = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PMBAC));
+	printk(KERN_INFO "PCI: PMBAM  = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PMBAM));
+	printk(KERN_INFO "PCI: PMBAT  = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PMBAT));
+
+	printk(KERN_INFO "PCI: PIOBA  = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PIOBA));
+	printk(KERN_INFO "PCI: PIOBAC = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PIOBAC));
+	printk(KERN_INFO "PCI: PIOBAM = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PIOBAM));
+	printk(KERN_INFO "PCI: PIOBAT = %08x\n", __raw_readl(KS8695_PCI_VA + KS8695_PIOBAT));
+}
+
+
+static struct hw_pci ks8695_pci __initdata = {
+	.nr_controllers	= 1,
+	.preinit	= ks8695_pci_preinit,
+	.setup		= ks8695_pci_setup,
+	.scan		= ks8695_pci_scan_bus,
+	.postinit	= NULL,
+	.swizzle	= pci_std_swizzle,
+	.map_irq	= NULL,
+};
+
+void __init ks8695_init_pci(struct ks8695_pci_cfg *cfg)
+{
+	if (__raw_readl(KS8695_PCI_VA + KS8695_CRCFRV) & CFRV_GUEST) {
+		printk("PCI: KS8695 in guest mode, not initialising\n");
+		return;
+	}
+
+	printk(KERN_INFO "PCI: Initialising\n");
+	ks8695_show_pciregs();
+
+	/* set Mode */
+	__raw_writel(cfg->mode << 29, KS8695_PCI_VA + KS8695_PBM);
+
+	ks8695_pci.map_irq = cfg->map_irq;	/* board-specific map_irq method */
+
+	pci_common_init(&ks8695_pci);
+}