From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: Date: Mon, 14 Aug 2017 14:09:35 -0400 From: Keith Busch To: Dongdong Liu Cc: helgaas@kernel.org, linux-pci@vger.kernel.org, gabriele.paoloni@huawei.com, charles.chenxin@huawei.com, linuxarm@huawei.com Subject: Re: [PATCH V2] PCI/DPC: Add eDPC support Message-ID: <20170814180935.GE7233@localhost.localdomain> References: <1500716399-85612-1-git-send-email-liudongdong3@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1500716399-85612-1-git-send-email-liudongdong3@huawei.com> List-ID: On Sat, Jul 22, 2017 at 05:39:59PM +0800, Dongdong Liu wrote: > This code is to add eDPC support. Get and print the RP PIO error > information when the trigger condition is RP PIO error. > > For more information on eDPC, view the PCI-SIG eDPC ECN here: > https://pcisig.com/sites/default/files/specification_documents/ECN_Enhanced_DPC_2012-11-19_final.pdf > > Signed-off-by: Dongdong Liu > --- > v1-->v2: Use a stack local variable instead of the allocated memory for > collecting RP PIO information. > Fix the condition of RP PIO error. > rebase on v4.13-rc1 > --- > drivers/pci/pcie/pcie-dpc.c | 160 ++++++++++++++++++++++++++++++++++++++++++ > include/uapi/linux/pci_regs.h | 10 +++ > 2 files changed, 170 insertions(+) > > diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c > index c39f32e..724c548 100644 > --- a/drivers/pci/pcie/pcie-dpc.c > +++ b/drivers/pci/pcie/pcie-dpc.c > @@ -16,11 +16,55 @@ > #include > #include "../pci.h" > > +struct rp_pio_header_log_regs { > + u32 dw0; > + u32 dw1; > + u32 dw2; > + u32 dw3; > +}; > + > +struct dpc_rp_pio_regs { > + u32 status; > + u32 mask; > + u32 severity; > + u32 syserror; > + u32 exception; > + > + struct rp_pio_header_log_regs header_log; > + u32 impspec_log; > + u32 tlp_prefix_log[4]; > + u32 log_size; > + u16 first_error; > +}; > + > struct dpc_dev { > struct pcie_device *dev; > struct work_struct work; > int cap_pos; > bool rp; > + u32 rp_pio_status; > +}; > + > +static const char * const rp_pio_error_string[] = { > + "Configuration Request received UR Completion", /* Bit Position 0 */ > + "Configuration Request received CA Completion", /* Bit Position 1 */ > + "Configuration Request Completion Timeout", /* Bit Position 2 */ > + NULL, > + NULL, > + NULL, > + NULL, > + NULL, > + "I/O Request received UR Completion", /* Bit Position 8 */ > + "I/O Request received CA Completion", /* Bit Position 9 */ > + "I/O Request Completion Timeout", /* Bit Position 10 */ > + NULL, > + NULL, > + NULL, > + NULL, > + NULL, > + "Memory Request received UR Completion", /* Bit Position 16 */ > + "Memory Request received CA Completion", /* Bit Position 17 */ > + "Memory Request Completion Timeout", /* Bit Position 18 */ > }; > > static int dpc_wait_rp_inactive(struct dpc_dev *dpc) > @@ -79,10 +123,121 @@ static void interrupt_event_handler(struct work_struct *work) > dpc_wait_link_inactive(pdev); > if (dpc->rp && dpc_wait_rp_inactive(dpc)) > return; > + if (dpc->rp && dpc->rp_pio_status) > + pci_write_config_dword(pdev, > + dpc->cap_pos + PCI_EXP_DPC_RP_PIO_STATUS, > + dpc->rp_pio_status); After clearing the status, you need to set dpc->rp_pio_status to 0 to prevent non-rp detected errors from logging stale events. Otherwise, this looks fine to me.