| Message ID | 167330063330.975161.12886268473522769039.stgit@djiang5-mobl3.local |
|---|---|
| State | Superseded |
| Headers | show |
| Series | cxl: Introduce HDM decoder emulation from DVSEC range registers | expand |
On Mon, 09 Jan 2023 14:43:54 -0700 Dave Jiang <dave.jiang@intel.com> wrote: > CXL rev3.0 spec 8.1.3 > RCDs may not have HDM register blocks. Create fake decoders based on CXL > PCIe DVSEC registers. The DVSEC Range Registers provide the memory range > for these decoder structs. For the RCD, there can be up to 2 decoders > depending on the DVSEC Capability register HDM_count. > > Signed-off-by: Dave Jiang <dave.jiang@intel.com> Second half of this patch seems to be an unrelated refactor... I missed that entirely when reviewing v1. > > --- > v2: > - Refactor to put error case out of line. (Jonathan) > - kdoc update. (Jonathan) > - Remove init_emulated_hdm_decoder(), duplicate of > cxl_setup_hdm_decoder_from_dvsec(). > --- > drivers/cxl/core/hdm.c | 37 ++++++++++++++++++++++++++++--------- > 1 file changed, 28 insertions(+), 9 deletions(-) > > diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c > index 165c0f382ce1..ed5e9ef3aa9b 100644 > --- a/drivers/cxl/core/hdm.c > +++ b/drivers/cxl/core/hdm.c > @@ -747,6 +747,13 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, > if (is_endpoint_decoder(&cxld->dev)) > cxled = to_cxl_endpoint_decoder(&cxld->dev); > > + if (!hdm) { > + if (!cxled) > + return -EINVAL; > + > + return cxl_setup_hdm_decoder_from_dvsec(port, cxld, which, info); > + } > + > ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); > base = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(which)); > size = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(which)); > @@ -840,19 +847,15 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, > return 0; > } I have no problem with what follows, but I can't see a clear connection to rest of the patch. > > -/** > - * devm_cxl_enumerate_decoders - add decoder objects per HDM register set > - * @cxlhdm: Structure to populate with HDM capabilities > - */ > -int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, > - struct cxl_endpoint_dvsec_info *info) Note the docs were wrong before this point... Probably fix them earlier. > +static void cxl_settle_decoders(struct cxl_hdm *cxlhdm) > { > void __iomem *hdm = cxlhdm->regs.hdm_decoder; > - struct cxl_port *port = cxlhdm->port; > - int i, committed; > - u64 dpa_base = 0; > + int committed, i; > u32 ctrl; > > + if (!hdm) > + return; > + > /* > * Since the register resource was recently claimed via request_region() > * be careful about trusting the "not-committed" status until the commit > @@ -869,6 +872,22 @@ int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, > /* ensure that future checks of committed can be trusted */ > if (committed != cxlhdm->decoder_count) > msleep(20); > +} > + > +/** > + * devm_cxl_enumerate_decoders - add decoder objects per HDM register set > + * @cxlhdm: Structure to populate with HDM capabilities > + * @info: cached DVSEC range register info > + */ > +int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, > + struct cxl_endpoint_dvsec_info *info) > +{ > + void __iomem *hdm = cxlhdm->regs.hdm_decoder; > + struct cxl_port *port = cxlhdm->port; > + int i; > + u64 dpa_base = 0; > + > + cxl_settle_decoders(cxlhdm); > > for (i = 0; i < cxlhdm->decoder_count; i++) { > int target_map[CXL_DECODER_MAX_INTERLEAVE] = { 0 }; > > >
diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c index 165c0f382ce1..ed5e9ef3aa9b 100644 --- a/drivers/cxl/core/hdm.c +++ b/drivers/cxl/core/hdm.c @@ -747,6 +747,13 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, if (is_endpoint_decoder(&cxld->dev)) cxled = to_cxl_endpoint_decoder(&cxld->dev); + if (!hdm) { + if (!cxled) + return -EINVAL; + + return cxl_setup_hdm_decoder_from_dvsec(port, cxld, which, info); + } + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); base = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(which)); size = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(which)); @@ -840,19 +847,15 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, return 0; } -/** - * devm_cxl_enumerate_decoders - add decoder objects per HDM register set - * @cxlhdm: Structure to populate with HDM capabilities - */ -int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, - struct cxl_endpoint_dvsec_info *info) +static void cxl_settle_decoders(struct cxl_hdm *cxlhdm) { void __iomem *hdm = cxlhdm->regs.hdm_decoder; - struct cxl_port *port = cxlhdm->port; - int i, committed; - u64 dpa_base = 0; + int committed, i; u32 ctrl; + if (!hdm) + return; + /* * Since the register resource was recently claimed via request_region() * be careful about trusting the "not-committed" status until the commit @@ -869,6 +872,22 @@ int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, /* ensure that future checks of committed can be trusted */ if (committed != cxlhdm->decoder_count) msleep(20); +} + +/** + * devm_cxl_enumerate_decoders - add decoder objects per HDM register set + * @cxlhdm: Structure to populate with HDM capabilities + * @info: cached DVSEC range register info + */ +int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, + struct cxl_endpoint_dvsec_info *info) +{ + void __iomem *hdm = cxlhdm->regs.hdm_decoder; + struct cxl_port *port = cxlhdm->port; + int i; + u64 dpa_base = 0; + + cxl_settle_decoders(cxlhdm); for (i = 0; i < cxlhdm->decoder_count; i++) { int target_map[CXL_DECODER_MAX_INTERLEAVE] = { 0 };
CXL rev3.0 spec 8.1.3 RCDs may not have HDM register blocks. Create fake decoders based on CXL PCIe DVSEC registers. The DVSEC Range Registers provide the memory range for these decoder structs. For the RCD, there can be up to 2 decoders depending on the DVSEC Capability register HDM_count. Signed-off-by: Dave Jiang <dave.jiang@intel.com> --- v2: - Refactor to put error case out of line. (Jonathan) - kdoc update. (Jonathan) - Remove init_emulated_hdm_decoder(), duplicate of cxl_setup_hdm_decoder_from_dvsec(). --- drivers/cxl/core/hdm.c | 37 ++++++++++++++++++++++++++++--------- 1 file changed, 28 insertions(+), 9 deletions(-)