[PATCH] cxl/pci: Change CXL AER support check to use native AER

From: Terry Bowman
Date: Thu Nov 02 2023 - 11:53:01 EST


Native CXL protocol errors are delivered to the OS through AER
reporting. The owner of AER owns CXL Protocol error management with
respect to _OSC negotiation.[1] CXL device errors are handled by a
separate interrupt with native control gated by _OSC control field
'CXL Memory Error Reporting Control'.

The CXL driver incorrectly checks for 'CXL Memory Error Reporting
Control' before accessing AER registers and caching RCH downport
AER registers. Replace the current check in these 2 cases with
native AER checks.

[1] CXL 3.0 - 9.17.2 CXL _OSC, Table-9-26, Interpretation of CXL
_OSC Support Fields, p.641

Fixes: 5d2ffbe4b81a ("cxl/port: Store the downstream port's Component Register mappings in struct cxl_dport")
Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>
Reviewed-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@xxxxxxx>
---
drivers/cxl/core/pci.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 01c441f2e25e..b29f6d09744b 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -812,7 +812,7 @@ static void cxl_disable_rch_root_ints(struct cxl_dport *dport)
* the root cmd register's interrupts is required. But, PCI spec
* shows these are disabled by default on reset.
*/
- if (bridge->native_cxl_error) {
+ if (bridge->native_aer) {
aer_cmd_mask = (PCI_ERR_ROOT_CMD_COR_EN |
PCI_ERR_ROOT_CMD_NONFATAL_EN |
PCI_ERR_ROOT_CMD_FATAL_EN);
@@ -828,7 +828,7 @@ void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport)
struct pci_host_bridge *host_bridge;

host_bridge = to_pci_host_bridge(dport_dev);
- if (host_bridge->native_cxl_error)
+ if (host_bridge->native_aer)
dport->rcrb.aer_cap = cxl_rcrb_to_aer(dport_dev, dport->rcrb.base);

dport->reg_map.host = host;
--
2.34.1