diff options
| author | Dave Jiang <dave.jiang@intel.com> | 2023-02-14 20:41:35 +0100 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2023-02-15 00:45:21 +0100 |
| commit | d7a2153762c7369534c432ac7e86996063e246df (patch) | |
| tree | 7ebad533e83f5218ebadcc7b66259b44f3a83f3d /drivers/cxl | |
| parent | cxl/hdm: Create emulated cxl_hdm for devices that do not have HDM decoders (diff) | |
| download | linux-d7a2153762c7369534c432ac7e86996063e246df.tar.xz linux-d7a2153762c7369534c432ac7e86996063e246df.zip | |
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>
Diffstat (limited to 'drivers/cxl')
| -rw-r--r-- | drivers/cxl/core/hdm.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c index a49543f22dca..39e02f28b6a6 100644 --- a/drivers/cxl/core/hdm.c +++ b/drivers/cxl/core/hdm.c @@ -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); |