cxl/hdm: Add emulation when HDM decoders are not committed

For the case where DVSEC range register(s) are active and HDM decoders are
not committed, use RR to provide emulation. A first pass is done to note
whether any decoders are committed. If there are no committed endpoint
decoders, then DVSEC ranges will be used for emulation.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/167640369536.935665.611974113442400127.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dave Jiang 2023-02-14 11:41:35 -08:00 committed by Dan Williams
parent 4474ce565e
commit d7a2153762

View File

@ -730,6 +730,32 @@ static int cxl_setup_hdm_decoder_from_dvsec(struct cxl_port *port,
return 0;
}
static bool should_emulate_decoders(struct cxl_port *port)
{
struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev);
void __iomem *hdm = cxlhdm->regs.hdm_decoder;
u32 ctrl;
int i;
if (!is_cxl_endpoint(cxlhdm->port))
return false;
if (!hdm)
return true;
/*
* If any decoders are committed already, there should not be any
* emulated DVSEC decoders.
*/
for (i = 0; i < cxlhdm->decoder_count; i++) {
ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i));
if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl))
return false;
}
return true;
}
static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
int *target_map, void __iomem *hdm, int which,
u64 *dpa_base, struct cxl_endpoint_dvsec_info *info)
@ -745,6 +771,9 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
unsigned char target_id[8];
} target_list;
if (should_emulate_decoders(port))
return cxl_setup_hdm_decoder_from_dvsec(port, cxld, which, info);
if (is_endpoint_decoder(&cxld->dev))
cxled = to_cxl_endpoint_decoder(&cxld->dev);