[PATCH 1/2] nios2: Add architectural support for PCIe

Ley Foon Tan
2015-09-22T07:19:43Z

This patch add pcie support on nios2 platform.

Signed-off-by: Ley Foon Tan <lftan@altera.com>
---
arch/nios2/Kconfig | 24 +++++++++++++++++++++
arch/nios2/include/asm/Kbuild | 2 +-
arch/nios2/include/asm/io.h | 11 +++++++++-
arch/nios2/include/asm/pci.h | 50 +++++++++++++++++++++++++++++++++++++++++++
arch/nios2/kernel/Makefile | 1 +
arch/nios2/kernel/pci.c | 33 ++++++++++++++++++++++++++++
6 files changed, 119 insertions(+), 2 deletions(-)
create mode 100644 arch/nios2/include/asm/pci.h
create mode 100644 arch/nios2/kernel/pci.c

diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index 4375554..9e0a291 100644
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -11,6 +11,7 @@ config NIOS2
select HAVE_ARCH_KGDB
select IRQ_DOMAIN
select MODULES_USE_ELF_RELA
+ select MIGHT_HAVE_PCI
select OF
select OF_EARLY_FLATTREE
select SOC_BUS
@@ -194,6 +195,29 @@ config NIOS2_IO_REGION_BASE

endmenu

+menu "Bus support"
+config PCI
+ bool "PCI support"
+ select GENERIC_PCI_IOMAP
+ help
+ This feature enables support for PCIe bus system. If you say Y
+ here, the kernel will include drivers and infrastructure code
+ to support PCIe bus devices.
+
+config PCI_DOMAINS
+ def_bool PCI
+
+config PCI_DOMAINS_GENERIC
+ def_bool PCI
+
+config PCI_SYSCALL
+ def_bool PCI
+
+source "drivers/pci/Kconfig"
+source "drivers/pci/pcie/Kconfig"
+
+endmenu
+
menu "Executable file formats"

source "fs/Kconfig.binfmt"
diff --git a/arch/nios2/include/asm/Kbuild b/arch/nios2/include/asm/Kbuild
index 914864e..8b928ba 100644
--- a/arch/nios2/include/asm/Kbuild
+++ b/arch/nios2/include/asm/Kbuild
@@ -34,8 +34,8 @@ generic-y += mm-arch-hooks.h
generic-y += mman.h
generic-y += module.h
generic-y += msgbuf.h
+generic-y += msi.h
generic-y += param.h
-generic-y += pci.h
generic-y += percpu.h
generic-y += poll.h
generic-y += posix_types.h
diff --git a/arch/nios2/include/asm/io.h b/arch/nios2/include/asm/io.h
index c5a62da..74ba082 100644
--- a/arch/nios2/include/asm/io.h
+++ b/arch/nios2/include/asm/io.h
@@ -14,7 +14,7 @@
#include <linux/types.h>
#include <asm/pgtable-bits.h>

-/* PCI is not supported in nios2, set this to 0. */
+/* PCI I/O space is not supported, set this to 0. */
#define IO_SPACE_LIMIT 0

#define readb_relaxed(addr) readb(addr)
@@ -45,6 +45,15 @@ static inline void iounmap(void __iomem *addr)
__iounmap(addr);
}

+static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
+{
+ return NULL;
+}
+
+static inline void ioport_unmap(void __iomem *p)
+{
+}
+
#define ioremap_wc ioremap_nocache
#define ioremap_wt ioremap_nocache

diff --git a/arch/nios2/include/asm/pci.h b/arch/nios2/include/asm/pci.h
new file mode 100644
index 0000000..f2cba05
--- /dev/null
+++ b/arch/nios2/include/asm/pci.h
@@ -0,0 +1,50 @@
+/* Copyright Altera Corporation (C) 2015. All rights reserved.
+ *
+ * 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.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef _ASM_NIOS2_PCI_H
+#define _ASM_NIOS2_PCI_H
+
+#ifdef __KERNEL__
+#include <linux/dma-mapping.h>
+
+#include <asm/io.h>
+#include <asm-generic/pci-bridge.h>
+#include <asm-generic/pci-dma-compat.h>
+
+#define PCIBIOS_MIN_IO 0UL
+#define PCIBIOS_MIN_MEM 0UL
+
+/*
+ * Set to 1 if the kernel should re-assign all PCI bus numbers
+ */
+#define pcibios_assign_all_busses() (pci_has_flag(PCI_REASSIGN_ALL_BUS))
+
+#ifdef CONFIG_PCI
+extern int isa_dma_bridge_buggy;
+#else
+#define isa_dma_bridge_buggy (0)
+#endif
+
+#ifdef CONFIG_PCI_DOMAINS
+static inline int pci_proc_domain(struct pci_bus *bus)
+{
+ return pci_domain_nr(bus);
+}
+#endif /* CONFIG_PCI_DOMAINS */
+
+#endif /* __KERNEL__ */
+
+#endif
diff --git a/arch/nios2/kernel/Makefile b/arch/nios2/kernel/Makefile
index 1aae257..bb1ef81 100644
--- a/arch/nios2/kernel/Makefile
+++ b/arch/nios2/kernel/Makefile
@@ -10,6 +10,7 @@ obj-y += entry.o
obj-y += insnemu.o
obj-y += irq.o
obj-y += nios2_ksyms.o
+obj-y += pci.o
obj-y += process.o
obj-y += prom.o
obj-y += ptrace.o
diff --git a/arch/nios2/kernel/pci.c b/arch/nios2/kernel/pci.c
new file mode 100644
index 0000000..d28aed7
--- /dev/null
+++ b/arch/nios2/kernel/pci.c
@@ -0,0 +1,33 @@
+/* Copyright Altera Corporation (C) 2015. All rights reserved.
+ *
+ * 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.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <linux/pci.h>
+
+/*
+ * Called after each bus is probed, but before its children are examined
+ */
+void pcibios_fixup_bus(struct pci_bus *bus)
+{
+ /* nothing to do, expected to be removed in the future */
+}
+
+/*
+ * 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;
+}
--
1.8.2.1