[PATCH v8 1/2] PCI support added to ARC

From: Joao Pinto
Date: Thu Feb 04 2016 - 10:52:29 EST


This patch adds PCI support to ARC and updates drivers/pci Makefile
enabling the ARC arch to use the generic PCI setup functions.

Signed-off-by: Joao Pinto <jpinto@xxxxxxxxxxxx>
---
Change v7 -> v8:
- Nothing changed (just to keep up with patch set version).
Change v6 -> v7 (Bjorn Helgaas):
- Parenthesis removed from definitions
Change v5 -> v6 (Vineet Gupta):
- Removed EXPORT_SYMBOL(pcibios_fixup_bus) from pcibios.c
Change v4 -> v5 (Vineet Gupta):
- pcibios.c unused functions, variables and includes were removed
- ioremap.c has no need for changes (no patch is necessary)
- pci.h unused functions and variables were removed
Change v3 -> v4:
- Nothing changed (just to keep up with patch set version).
Change v2 -> v3 (Bjorn Helgaas):
- arch/arc/kernel/pcibios.c unused functions were removed and also the
arch/arc/include/asm/mach/pci.h was removed because was no longer necessary
Change v1 -> v2:
- In arch/arc/Kconfig, the new menu entry (Bus Configuration) was moved to the
slot between sourcing of drivers/Kconfig and fs/Kconfig (Vineet Gupta)
- In arch/arc/plat-axs10x/Kconfig the "select MIGHT_HAVE_PCI" option was placed
in order as suggested (Vineet Gupta)
- ioport_map() and ioport_unmap() were static inlined and included in
the io.h (Vineet Gupta)
- pcibios_min_io and pcibios_min_mem declaration moved to
pcibios.c (Vineet Gupta)
- pr_err() replaced by dev_err() in pcibios_enable_device() (Bjorn Helgaas)
- string simplified in pcibios_enable_device() (Vineet Gupta)
- pci_host_bridge_window structure was replaced by resource_entry structure, and
list_for_each_entry() for resource_list_for_each_entry() in pcibios.c

arch/arc/Kconfig | 23 +++++++++++++++++++++++
arch/arc/include/asm/dma.h | 5 +++++
arch/arc/include/asm/io.h | 9 +++++++++
arch/arc/include/asm/pci.h | 31 +++++++++++++++++++++++++++++++
arch/arc/kernel/Makefile | 1 +
arch/arc/kernel/pcibios.c | 23 +++++++++++++++++++++++
arch/arc/plat-axs10x/Kconfig | 1 +
drivers/pci/Makefile | 1 +
8 files changed, 94 insertions(+)
create mode 100644 arch/arc/include/asm/pci.h
create mode 100644 arch/arc/kernel/pcibios.c

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 2c2ac3f..98b32c1 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -19,6 +19,7 @@ config ARC
select GENERIC_FIND_FIRST_BIT
# for now, we don't need GENERIC_IRQ_PROBE, CONFIG_GENERIC_IRQ_CHIP
select GENERIC_IRQ_SHOW
+ select GENERIC_PCI_IOMAP
select GENERIC_PENDING_IRQ if SMP
select GENERIC_SMP_IDLE_THREAD
select HAVE_ARCH_KGDB
@@ -39,6 +40,9 @@ config ARC
select PERF_USE_VMALLOC
select HAVE_DEBUG_STACKOVERFLOW

+config MIGHT_HAVE_PCI
+ bool
+
config TRACE_IRQFLAGS_SUPPORT
def_bool y

@@ -570,6 +574,25 @@ endmenu # "ARC Architecture Configuration"
source "mm/Kconfig"
source "net/Kconfig"
source "drivers/Kconfig"
+
+menu "Bus Support"
+
+config PCI
+ bool "PCI support" if MIGHT_HAVE_PCI
+ help
+ PCI is the name of a bus system, i.e. the way the CPU talks to the other stuff inside
+ your box.Find out if your board/platform have PCI.
+ Note: PCIE support for Synopsys Device will be available only when
+ HAPS DX is configured with PCIE RC bitmap. If you have PCI, say Y, otherwise N.
+
+config PCI_SYSCALL
+ def_bool PCI
+
+source "drivers/pci/Kconfig"
+source "drivers/pci/pcie/Kconfig"
+
+endmenu
+
source "fs/Kconfig"
source "arch/arc/Kconfig.debug"
source "security/Kconfig"
diff --git a/arch/arc/include/asm/dma.h b/arch/arc/include/asm/dma.h
index ca7c451..01e47a6 100644
--- a/arch/arc/include/asm/dma.h
+++ b/arch/arc/include/asm/dma.h
@@ -10,5 +10,10 @@
#define ASM_ARC_DMA_H

#define MAX_DMA_ADDRESS 0xC0000000
+#ifdef CONFIG_PCI
+extern int isa_dma_bridge_buggy;
+#else
+#define isa_dma_bridge_buggy 0
+#endif

#endif
diff --git a/arch/arc/include/asm/io.h b/arch/arc/include/asm/io.h
index 694ece8..947bf0c 100644
--- a/arch/arc/include/asm/io.h
+++ b/arch/arc/include/asm/io.h
@@ -16,6 +16,15 @@
extern void __iomem *ioremap(unsigned long physaddr, unsigned long size);
extern void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
unsigned long flags);
+static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
+{
+ return (void __iomem *)port;
+}
+
+static inline void ioport_unmap(void __iomem *addr)
+{
+}
+
extern void iounmap(const void __iomem *addr);

#define ioremap_nocache(phy, sz) ioremap(phy, sz)
diff --git a/arch/arc/include/asm/pci.h b/arch/arc/include/asm/pci.h
new file mode 100644
index 0000000..2f2011c
--- /dev/null
+++ b/arch/arc/include/asm/pci.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2015-2016 Synopsys, Inc. (www.synopsys.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.
+ */
+
+#ifndef _ASM_ARC_PCI_H
+#define _ASM_ARC_PCI_H
+
+#ifdef __KERNEL__
+#include <asm-generic/pci-dma-compat.h>
+#include <asm-generic/pci-bridge.h>
+
+#include <linux/ioport.h>
+
+#define PCIBIOS_MIN_IO 0x100
+#define PCIBIOS_MIN_MEM 0x100000
+
+#define pcibios_assign_all_busses() 1
+/*
+ * The PCI address space does equal the physical memory address space.
+ * The networking and block device layers use this boolean for bounce
+ * buffer decisions.
+ */
+#define PCI_DMA_BUS_IS_PHYS 1
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_ARC_PCI_H */
diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile
index e7f3625..1bc2036 100644
--- a/arch/arc/kernel/Makefile
+++ b/arch/arc/kernel/Makefile
@@ -12,6 +12,7 @@ obj-y := arcksyms.o setup.o irq.o time.o reset.o ptrace.o process.o devtree.o
obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o clk.o
obj-$(CONFIG_ISA_ARCOMPACT) += entry-compact.o intc-compact.o
obj-$(CONFIG_ISA_ARCV2) += entry-arcv2.o intc-arcv2.o
+obj-$(CONFIG_PCI) += pcibios.o

obj-$(CONFIG_MODULES) += arcksyms.o module.o
obj-$(CONFIG_SMP) += smp.o
diff --git a/arch/arc/kernel/pcibios.c b/arch/arc/kernel/pcibios.c
new file mode 100644
index 0000000..7bc3a42
--- /dev/null
+++ b/arch/arc/kernel/pcibios.c
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2014-2015 Synopsys, Inc. (www.synopsys.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 <linux/pci.h>
+
+/*
+ * We don't have to worry about legacy ISA devices, so nothing to do here
+ */
+resource_size_t pcibios_align_resource(void *data, const struct resource *res,
+ resource_size_t size, resource_size_t align)
+{
+ return res->start;
+}
+
+void pcibios_fixup_bus(struct pci_bus *bus)
+{
+}
diff --git a/arch/arc/plat-axs10x/Kconfig b/arch/arc/plat-axs10x/Kconfig
index d475f9d..426ac4b 100644
--- a/arch/arc/plat-axs10x/Kconfig
+++ b/arch/arc/plat-axs10x/Kconfig
@@ -11,6 +11,7 @@ menuconfig ARC_PLAT_AXS10X
select DW_APB_ICTL
select GPIO_DWAPB
select OF_GPIO
+ select MIGHT_HAVE_PCI
select GENERIC_IRQ_CHIP
select ARCH_REQUIRE_GPIOLIB
help
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index be3f631..2154092 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_PCI_IOV) += iov.o
# Some architectures use the generic PCI setup functions
#
obj-$(CONFIG_ALPHA) += setup-irq.o
+obj-$(CONFIG_ARC) += setup-irq.o
obj-$(CONFIG_ARM) += setup-irq.o
obj-$(CONFIG_ARM64) += setup-irq.o
obj-$(CONFIG_UNICORE32) += setup-irq.o
--
1.8.1.5