Re: [PATCH] PCI: designware: fix asynchronous external abort in keystone PCIe h/w

From: Joao Pinto
Date: Tue Jan 10 2017 - 05:26:42 EST


Hi,

Às 4:41 PM de 1/9/2017, Murali Karicheri escreveu:
> On 01/04/2017 02:32 PM, Murali Karicheri wrote:
>> Recent fixes for iATU unroll support introduced a bug that causes
>> asynchronous external abort in Keystone PCIe h/w which doesn't have
>> ATU port and the corresponding register. So the check should be moved
>> below where dw_pcie_prog_outbound_atu() is called to avoid that
>> being called on keystine PCIe h/w.
>>
>> Here is the backtrace
>>
>> [ 0.771174] OF: PCI: MEM 0x60000000..0x6fffffff -> 0x60000000
>> [ 0.778118] Unhandled fault: asynchronous external abort (0x1211) at 0x00000000
>> [ 0.785548] pgd = c0003000
>> [ 0.788347] [00000000] *pgd=80000800004003, *pmd=00000000
>> [ 0.793864] Internal error: : 1211 [#1] PREEMPT SMP ARM
>> [ 0.799197] Modules linked in:
>> [ 0.802351] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.9.0-00009-g6ff59d2-dirty #7
>> [ 0.810130] Hardware name: Keystone
>> [ 0.813717] task: eb878000 task.stack: eb866000
>> [ 0.818356] PC is at dw_pcie_setup_rc+0x24/0x380
>> [ 0.823083] LR is at ks_pcie_host_init+0x10/0x170
>>
>> Fixes: 416379f9ebde ("PCI: designware: Check for iATU unroll support after initializing host")
>> Signed-off-by: Murali Karicheri <m-karicheri2@xxxxxx>
>> Tested-by: Kishon Vijay Abraham I <kishon@xxxxxx>
>> ---
>> - Applies to pci/master
>> - Bug was introduced in v4.9
>> - Tested on K2E EVM with SATA and DRA7-EVM with an intel PCI ethernet card
>>
>> drivers/pci/host/pcie-designware.c | 10 +++++-----
>> 1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
>> index bed1999..af8f6e9 100644
>> --- a/drivers/pci/host/pcie-designware.c
>> +++ b/drivers/pci/host/pcie-designware.c
>> @@ -807,11 +807,6 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
>> {
>> u32 val;
>>
>> - /* get iATU unroll support */
>> - pp->iatu_unroll_enabled = dw_pcie_iatu_unroll_enabled(pp);
>> - dev_dbg(pp->dev, "iATU unroll: %s\n",
>> - pp->iatu_unroll_enabled ? "enabled" : "disabled");
>> -
>> /* set the number of lanes */
>> val = dw_pcie_readl_rc(pp, PCIE_PORT_LINK_CONTROL);
>> val &= ~PORT_LINK_MODE_MASK;
>> @@ -882,6 +877,11 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
>> * we should not program the ATU here.
>> */
>> if (!pp->ops->rd_other_conf) {
>> + /* get iATU unroll support */
>> + pp->iatu_unroll_enabled = dw_pcie_iatu_unroll_enabled(pp);
>> + dev_dbg(pp->dev, "iATU unroll: %s\n",
>> + pp->iatu_unroll_enabled ? "enabled" : "disabled");
>> +
>> dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
>> PCIE_ATU_TYPE_MEM, pp->mem_base,
>> pp->mem_bus_addr, pp->mem_size);
>>
> Bjorn,
>
> A Gentle ping to merge this important fix to v4.10-rc kernel for Keystone PCI as
> it is broken since v4.9.
>

In my understanding your proposal will have no impact in platform using ATU, so
for me is fine.

Acked-By: Joao Pinto <jpinto@xxxxxxxxxxxx>

> Thanks
>