Bowman, Terry wrote: > > > > On 1/14/2025 4:02 PM, Ira Weiny wrote: > > Terry Bowman wrote: > >> Add logic to map CXL PCIe Upstream Switch Port (USP) RAS registers. > >> > >> Introduce 'struct cxl_regs' member into 'struct cxl_port' to cache a > >> pointer to the CXL Upstream Port's mapped RAS registers. > >> > >> Also, introduce cxl_uport_init_ras_reporting() to perform the USP RAS > >> register mapping. This is similar to the existing > >> cxl_dport_init_ras_reporting() but for USP devices. > >> > >> The USP may have multiple downstream endpoints. Before mapping AER > >> registers check if the registers are already mapped. > >> > >> Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx> > >> --- > >> drivers/cxl/core/pci.c | 15 +++++++++++++++ > >> drivers/cxl/cxl.h | 4 ++++ > >> drivers/cxl/mem.c | 8 ++++++++ > >> 3 files changed, 27 insertions(+) > >> > >> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c > >> index 1af2d0a14f5d..97e6a15bea88 100644 > >> --- a/drivers/cxl/core/pci.c > >> +++ b/drivers/cxl/core/pci.c > >> @@ -773,6 +773,21 @@ static void cxl_disable_rch_root_ints(struct cxl_dport *dport) > >> writel(aer_cmd, aer_base + PCI_ERR_ROOT_COMMAND); > >> } > >> > >> +void cxl_uport_init_ras_reporting(struct cxl_port *port) > >> +{ > >> + /* uport may have more than 1 downstream EP. Check if already mapped. */ > >> + if (port->uport_regs.ras) > >> + return; > >> + > >> + port->reg_map.host = &port->dev; > >> + if (cxl_map_component_regs(&port->reg_map, &port->uport_regs, > >> + BIT(CXL_CM_CAP_CAP_ID_RAS))) { > >> + dev_err(&port->dev, "Failed to map RAS capability.\n"); > >> + return; > > Why return here? Actually I think 8/16 had the same issue now that I see > > this. > > > > Other than that: > > > > Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx> > > > > [snip] > If RAS registers fail mapping then exit to avoid CXL Port error handler initialization. > The CXL Port error handlers rely on RAS registers for logging and without mapped RAS > registers the error handlers will return immediately. Sorry I was not clear and I should not have clipped the text so much. You return in a block which is at the end of the function: +void cxl_uport_init_ras_reporting(struct cxl_port *port) +{ + /* uport may have more than 1 downstream EP. Check if already mapped. */ + if (port->uport_regs.ras) + return; + + port->reg_map.host = &port->dev; + if (cxl_map_component_regs(&port->reg_map, &port->uport_regs, + BIT(CXL_CM_CAP_CAP_ID_RAS))) { + dev_err(&port->dev, "Failed to map RAS capability.\n"); + return; + } +} So no need for this specific statement? Ira