Re: [PATCH v6 1/2] PCI support added to ARC

[Joao Pinto]

Hi Bjorn,

Thank you for the review. I am going to update the needed points and send a new
patch version until tomorrow.

Joao

On 1/29/2016 8:40 PM, Bjorn Helgaas wrote:
> Hi Joao,
> 
> Trivial nits below; I wouldn't even mention them if you weren't making
> a few updates to the other patch.
> 
> On Thu, Jan 14, 2016 at 11:04:32AM +0000, Joao Pinto wrote:
>> 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 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, 95 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..37942fa 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)
> 
> No parens needed around "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..2f091e1
>> --- /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)
> 
> Or around "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-$(CONFIG_SMP) 			+= smp.o
>> diff --git a/arch/arc/kernel/pcibios.c b/arch/arc/kernel/pcibios.c
>> new file mode 100644
>> index 0000000..12ea45a
>> --- /dev/null
>> +++ b/arch/arc/kernel/pcibios.c
>> @@ -0,0 +1,23 @@
>> +/*
>> + * Copyright (C) 2014-2015 Synopsys, Inc. (www.synopsys.com)
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + *
>> + */
>> +
>> +#include <linux/pci.h>
>> +
>> +/*
>> + * We don't have to worry about legacy ISA devices, so nothing to do here
>> + */
>> +resource_size_t pcibios_align_resource(void *data, const struct resource *res,
>> +				resource_size_t size, resource_size_t align)
>> +{
>> +	return res->start;
>> +}
>> +
>> +void pcibios_fixup_bus(struct pci_bus *bus)
>> +{
>> +}
>> diff --git a/arch/arc/plat-axs10x/Kconfig b/arch/arc/plat-axs10x/Kconfig
>> index d475f9d..426ac4b 100644
>> --- a/arch/arc/plat-axs10x/Kconfig
>> +++ b/arch/arc/plat-axs10x/Kconfig
>> @@ -11,6 +11,7 @@ menuconfig ARC_PLAT_AXS10X
>>  	select DW_APB_ICTL
>>  	select GPIO_DWAPB
>>  	select OF_GPIO
>> +	select MIGHT_HAVE_PCI
>>  	select GENERIC_IRQ_CHIP
>>  	select ARCH_REQUIRE_GPIOLIB
>>  	help
>> diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
>> index be3f631..2154092 100644
>> --- a/drivers/pci/Makefile
>> +++ b/drivers/pci/Makefile
>> @@ -32,6 +32,7 @@ obj-$(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