[PATCH v3 2/3] openrisc: Add pci bus support

From: Stafford Horne
Date: Sun Jul 24 2022 - 22:08:24 EST


This patch adds required definitions to allow for PCI buses on OpenRISC.
This is being tested on the OpenRISC QEMU virt platform which is in
development.

OpenRISC does not have IO ports so we keep the definition of
IO_SPACE_LIMIT and PIO_RESERVED to be 0.

Note, since commit 66bcd06099bb ("parport_pc: Also enable driver for PCI
systems") all platforms that support PCI also need to support parallel
port. We add a generic header to support compiling parallel port
drivers, though they generally will not work as they require IO ports.

Signed-off-by: Stafford Horne <shorne@xxxxxxxxx>
---
arch/openrisc/Kconfig | 5 ++++-
arch/openrisc/include/asm/Kbuild | 1 +
arch/openrisc/include/asm/io.h | 2 +-
3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index e814df4c483c..c7f282f60f64 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -20,8 +20,9 @@ config OPENRISC
select GENERIC_IRQ_CHIP
select GENERIC_IRQ_PROBE
select GENERIC_IRQ_SHOW
- select GENERIC_IOMAP
+ select GENERIC_PCI_IOMAP
select GENERIC_CPU_DEVICES
+ select HAVE_PCI
select HAVE_UID16
select GENERIC_ATOMIC64
select GENERIC_CLOCKEVENTS_BROADCAST
@@ -32,6 +33,8 @@ config OPENRISC
select CPU_NO_EFFICIENT_FFS if !OPENRISC_HAVE_INST_FF1
select ARCH_USE_QUEUED_RWLOCKS
select OMPIC if SMP
+ select PCI_DOMAINS_GENERIC if PCI
+ select PCI_MSI if PCI
select ARCH_WANT_FRAME_POINTERS
select GENERIC_IRQ_MULTI_HANDLER
select MMU_GATHER_NO_RANGE if MMU
diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild
index 3386b9c1c073..c8c99b554ca4 100644
--- a/arch/openrisc/include/asm/Kbuild
+++ b/arch/openrisc/include/asm/Kbuild
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
generic-y += extable.h
generic-y += kvm_para.h
+generic-y += parport.h
generic-y += spinlock_types.h
generic-y += spinlock.h
generic-y += qrwlock_types.h
diff --git a/arch/openrisc/include/asm/io.h b/arch/openrisc/include/asm/io.h
index c298061c70a7..625ac6ad1205 100644
--- a/arch/openrisc/include/asm/io.h
+++ b/arch/openrisc/include/asm/io.h
@@ -17,7 +17,7 @@
#include <linux/types.h>

/*
- * PCI: can we really do 0 here if we have no port IO?
+ * PCI: We do not use IO ports in OpenRISC
*/
#define IO_SPACE_LIMIT 0

--
2.36.1