Re: [PATCH v3 12/26] PCI: keystone: Prevent ARM32 specific code to be compiled for ARM64

From: Kishon Vijay Abraham I <kishon@ti.com>
To: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Rob Herring <robh+dt@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Murali Karicheri <m-karicheri2@ti.com>,
	Jingoo Han <jingoohan1@gmail.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	<linux-pci@vger.kernel.org>, <devicetree@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>, <linux-omap@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-arm-kernel@axis.com>,
	Minghuan Lian <minghuan.Lian@nxp.com>,
	Mingkai Hu <mingkai.hu@nxp.com>, Roy Zang <roy.zang@nxp.com>,
	Jesper Nilsson <jesper.nilsson@axis.com>
Subject: Re: [PATCH v3 12/26] PCI: keystone: Prevent ARM32 specific code to be compiled for ARM64
Date: Fri, 12 Apr 2019 14:20:06 +0530	[thread overview]
Message-ID: <ee9d27e6-c653-4965-b552-3cf1ce5bdf51@ti.com> (raw)
In-Reply-To: <20190411150332.GC6862@red-moon>

Hi Lorenzo,

On 11/04/19 8:33 PM, Lorenzo Pieralisi wrote:
> On Mon, Mar 25, 2019 at 03:09:33PM +0530, Kishon Vijay Abraham I wrote:
>> hook_fault_code is an ARM32 specific API for hooking into data abort.
>> Since pci-keystone.c will be used for AM65X platforms which is an
>> ARM64 platform,
> 
> Hi Kishon,
> 
> How is the problem plugged by the fault hook fixed on ARM64 ?

At least in AM654 platform, I don't see a bus error when PCIe device is not
connected but returns 0xffffffff. So there is no necessary for hook_fault_code
in AM654 platform.

Thanks
Kishon

> 
> Thanks,
> Lorenzo
> 
>> allow hook_fault_code to be compiled only for ARM32.
>>
>> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
>> ---
>>  drivers/pci/controller/dwc/pci-keystone.c | 4 ++++
>>  1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
>> index dfe54553d832..93296d434f40 100644
>> --- a/drivers/pci/controller/dwc/pci-keystone.c
>> +++ b/drivers/pci/controller/dwc/pci-keystone.c
>> @@ -710,6 +710,7 @@ static int ks_pcie_config_legacy_irq(struct keystone_pcie *ks_pcie)
>>  	return ret;
>>  }
>>  
>> +#ifdef CONFIG_ARM
>>  /*
>>   * When a PCI device does not exist during config cycles, keystone host gets a
>>   * bus error instead of returning 0xffffffff. This handler always returns 0
>> @@ -729,6 +730,7 @@ static int ks_pcie_fault(unsigned long addr, unsigned int fsr,
>>  
>>  	return 0;
>>  }
>> +#endif
>>  
>>  static int __init ks_pcie_init_id(struct keystone_pcie *ks_pcie)
>>  {
>> @@ -778,12 +780,14 @@ static int __init ks_pcie_host_init(struct pcie_port *pp)
>>  	if (ret < 0)
>>  		return ret;
>>  
>> +#ifdef CONFIG_ARM
>>  	/*
>>  	 * PCIe access errors that result into OCP errors are caught by ARM as
>>  	 * "External aborts"
>>  	 */
>>  	hook_fault_code(17, ks_pcie_fault, SIGBUS, 0,
>>  			"Asynchronous external abort");
>> +#endif
>>  
>>  	ks_pcie_start_link(pci);
>>  	dw_pcie_wait_for_link(pci);
>> -- 
>> 2.17.1
>>