mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-12 21:57:43 +00:00
Code Issues Releases Wiki Activity

cxl/pci: Disable root port interrupts in RCH mode

Browse source 
The RCH root port contains root command AER registers that should not be
enabled.[1] Disable these to prevent root port interrupts.

[1] CXL 3.0 - 12.2.1.1 RCH Downstream Port-detected Errors

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Signed-off-by: Robert Richter <rrichter@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20231018171713.1883517-17-rrichter@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Terry Bowman 2023-10-18 19:17:09 +02:00 committed by Dan Williams
parent 6ac07883db
commit d1a9def33d
1 changed files with 32 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

32
drivers/cxl/core/pci.c
View file

@ -763,6 +763,35 @@ static void cxl_dport_map_regs(struct cxl_dport *dport)
cxl_dport_map_rch_aer(dport);
}
static void cxl_disable_rch_root_ints(struct cxl_dport *dport)
{
void __iomem *aer_base = dport->regs.dport_aer;
struct pci_host_bridge *bridge;
u32 aer_cmd_mask, aer_cmd;
if (!aer_base)
return;
bridge = to_pci_host_bridge(dport->dport_dev);
/*
* Disable RCH root port command interrupts.
* CXL 3.0 12.2.1.1 - RCH Downstream Port-detected Errors
*
* This sequence may not be necessary. CXL spec states disabling
* the root cmd register's interrupts is required. But, PCI spec
* shows these are disabled by default on reset.
*/
if (bridge->native_cxl_error) {
aer_cmd_mask = (PCI_ERR_ROOT_CMD_COR_EN |
PCI_ERR_ROOT_CMD_NONFATAL_EN |
PCI_ERR_ROOT_CMD_FATAL_EN);
aer_cmd = readl(aer_base + PCI_ERR_ROOT_COMMAND);
aer_cmd &= ~aer_cmd_mask;
writel(aer_cmd, aer_base + PCI_ERR_ROOT_COMMAND);
}
}
void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport)
{
struct device *dport_dev = dport->dport_dev;
@ -774,6 +803,9 @@ void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport)
dport->reg_map.host = host;
cxl_dport_map_regs(dport);
if (dport->rch)
cxl_disable_rch_root_ints(dport);
}
EXPORT_SYMBOL_NS_GPL(cxl_setup_parent_dport, CXL);