Patchwork [U-Boot,06/10] MIPS: qemu-malta: add PCI support

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Submitter Gabor Juhos
Date Jan. 23, 2013, 5:05 p.m.
Message ID <1358960705-25559-7-git-send-email-juhosg@openwrt.org>
Download mbox | patch
Permalink /patch/215004/
State Superseded
Delegated to: Daniel Schwierzeck
Headers show

Comments

Gabor Juhos - Jan. 23, 2013, 5:05 p.m.
Qemu emulates the Galileo GT64120 System Controller
which provides a CPU bus to PCI bus bridge.

The patch adds driver for this bridge and enables
PCI support for the emulated Malta board.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
---
Changes since RFC:
  - use a C struct to define the register layout instead
    of using a base address plus offset notation
  - remove custom IO accessors
---
 board/qemu-malta/Makefile    |    5 +-
 board/qemu-malta/pci.c       |  168 ++++++++++++++++++++++++++++++++++++++++++
 include/configs/qemu-malta.h |    6 ++
 3 files changed, 178 insertions(+), 1 deletion(-)
 create mode 100644 board/qemu-malta/pci.c

Patch

diff --git a/board/qemu-malta/Makefile b/board/qemu-malta/Makefile
index 6251bb8..59c1b1d 100644
--- a/board/qemu-malta/Makefile
+++ b/board/qemu-malta/Makefile
@@ -25,7 +25,10 @@  include $(TOPDIR)/config.mk
 
 LIB	= $(obj)lib$(BOARD).o
 
-COBJS	= $(BOARD).o
+COBJS-y			+= $(BOARD).o
+COBJS-$(CONFIG_PCI)	+= pci.o
+
+COBJS   := $(COBJS-y)
 SOBJS	= lowlevel_init.o
 
 SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
diff --git a/board/qemu-malta/pci.c b/board/qemu-malta/pci.c
new file mode 100644
index 0000000..fd9193b
--- /dev/null
+++ b/board/qemu-malta/pci.c
@@ -0,0 +1,168 @@ 
+/*
+ * Copyright (C) 2013 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * Based on the Linux implementation.
+ *   Copyright (C) 1999, 2000, 2004  MIPS Technologies, Inc.
+ *   Authors: Carsten Langgaard <carstenl@mips.com>
+ *            Maciej W. Rozycki <macro@mips.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <common.h>
+#include <asm/addrspace.h>
+#include <asm/gt64120.h>
+#include <asm/malta.h>
+#include <asm/io.h>
+#include <pci.h>
+
+#define PCI_ACCESS_READ  0
+#define PCI_ACCESS_WRITE 1
+
+struct gt64120_regs {
+	u8	unused_000[0xc18];
+	u32	intrcause;
+	u8	unused_c1c[0x0dc];
+	u32	pci0_cfgaddr;
+	u32	pci0_cfgdata;
+};
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static struct gt64120_regs *gt_regs;
+
+/*
+ * PCI controller "hose" value
+ */
+static struct pci_controller hose;
+
+#define GT_INTRCAUSE_ABORT_BITS	\
+		(GT_INTRCAUSE_MASABORT0_BIT | GT_INTRCAUSE_TARABORT0_BIT)
+
+static int gt_config_access(unsigned char access_type, pci_dev_t bdf,
+			    int where, u32 *data)
+{
+	unsigned int bus = PCI_BUS(bdf);
+	unsigned int dev = PCI_DEV(bdf);
+	unsigned int devfn = PCI_DEV(bdf) << 3 | PCI_FUNC(bdf);
+	u32 intr;
+	u32 addr;
+	u32 val;
+
+	if (bus == 0 && dev >= 31) {
+		/* Because of a bug in the galileo (for slot 31). */
+		return -1;
+	}
+
+	if (access_type == PCI_ACCESS_WRITE)
+		debug("PCI WR %02x:%02x.%x reg:%02d data:%08x\n",
+		       PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf),
+		       where, *data);
+
+	/* Clear cause register bits */
+	__raw_writel(~GT_INTRCAUSE_ABORT_BITS, &gt_regs->intrcause);
+
+	addr = GT_PCI0_CFGADDR_CONFIGEN_BIT;
+	addr |=	bus << GT_PCI0_CFGADDR_BUSNUM_SHF;
+	addr |=	devfn << GT_PCI0_CFGADDR_FUNCTNUM_SHF;
+	addr |= (where / 4) << GT_PCI0_CFGADDR_REGNUM_SHF;
+
+	/* Setup address */
+	__raw_writel(addr, &gt_regs->pci0_cfgaddr);
+
+	if (access_type == PCI_ACCESS_WRITE) {
+		if (bus == 0 && dev == 0) {
+			/*
+			 * The Galileo system controller is acting
+			 * differently than other devices.
+			 */
+			val = *data;
+		} else
+			val = cpu_to_le32(*data);
+
+		__raw_writel(val, &gt_regs->pci0_cfgdata);
+	} else {
+		val = __raw_readl(&gt_regs->pci0_cfgdata);
+
+		if (bus == 0 && dev == 0) {
+			/*
+			 * The Galileo system controller is acting
+			 * differently than other devices.
+			 */
+			*data = val;
+		} else
+			*data = le32_to_cpu(val);
+	}
+
+	/* Check for master or target abort */
+	intr = __raw_readl(&gt_regs->intrcause);
+	if (intr & GT_INTRCAUSE_ABORT_BITS) {
+		/* Error occurred, clear abort bits */
+		__raw_writel(~GT_INTRCAUSE_ABORT_BITS, &gt_regs->intrcause);
+		return -1;
+	}
+
+	if (access_type == PCI_ACCESS_READ)
+		debug("PCI RD %02x:%02x.%x reg:%02d data:%08x\n",
+		      PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf), where, *data);
+
+	return 0;
+}
+
+static int gt_read_config_dword(struct pci_controller *hose, pci_dev_t dev,
+				int where, u32 *value)
+{
+	*value = 0xffffffff;
+	return gt_config_access(PCI_ACCESS_READ, dev, where, value);
+}
+
+static int gt_write_config_dword(struct pci_controller *hose, pci_dev_t dev,
+				 int where, u32 value)
+{
+	u32 data = value;
+
+	return gt_config_access(PCI_ACCESS_WRITE, dev, where, &data);
+}
+
+void pci_init_board(void)
+{
+	set_io_port_base(CKSEG1ADDR(MALTA_IO_PORT_BASE));
+
+	gt_regs = (struct gt64120_regs *) CKSEG1ADDR(MALTA_GT_BASE);
+
+	hose.first_busno = 0;
+	hose.last_busno = 0xff;
+
+	/* System memory space */
+	pci_set_region(&hose.regions[0],
+		       0x00000000, 0x00000000,
+		       CONFIG_SYS_MEM_SIZE,
+		       PCI_REGION_MEM | PCI_REGION_SYS_MEMORY);
+
+	/* PCI memory space */
+	pci_set_region(&hose.regions[1],
+		       0x10000000, 0x10000000,
+		       128 * 1024 * 1024,
+		       PCI_REGION_MEM);
+
+	/* PCI I/O space */
+	pci_set_region(&hose.regions[2],
+		       0x0000000, 0x0000000,
+		       0x20000,
+		       PCI_REGION_IO);
+
+	hose.region_count = 3;
+
+	pci_set_ops(&hose,
+		    pci_hose_read_config_byte_via_dword,
+		    pci_hose_read_config_word_via_dword,
+		    gt_read_config_dword,
+		    pci_hose_write_config_byte_via_dword,
+		    pci_hose_write_config_word_via_dword,
+		    gt_write_config_dword);
+
+	pci_register_hose(&hose);
+	hose.last_busno = pci_hose_scan(&hose);
+}
diff --git a/include/configs/qemu-malta.h b/include/configs/qemu-malta.h
index 881c15d..36b584a 100644
--- a/include/configs/qemu-malta.h
+++ b/include/configs/qemu-malta.h
@@ -17,6 +17,9 @@ 
  */
 #define CONFIG_QEMU_MALTA
 
+#define CONFIG_PCI
+#define CONFIG_PCI_PNP
+
 /*
  * CPU Configuration
  */
@@ -30,6 +33,7 @@ 
 
 #define CONFIG_SWAP_IO_SPACE
 
+
 /*
  * Memory map
  */
@@ -108,6 +112,8 @@ 
 #undef CONFIG_CMD_NET
 #undef CONFIG_CMD_NFS
 
+#define CONFIG_CMD_PCI
+
 #define CONFIG_SYS_LONGHELP		/* verbose help, undef to save memory */
 
 #endif /* _QEMU_MALTA_CONFIG_H */