On 8/16/24 7:44 AM, ira.weiny@xxxxxxxxx wrote: > From: Navneet Singh <navneet.singh@xxxxxxxxx> > > Endpoint decoder mode is used to represent the partition the decoder > points to such as ram or pmem. > > Expand the mode to allow a decoder to point to a specific DC partition > (Region). > > Signed-off-by: Navneet Singh <navneet.singh@xxxxxxxxx> > Co-developed-by: Ira Weiny <ira.weiny@xxxxxxxxx> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx> > > --- > Changes: > [Fan: change mode range logic] > [Fan: use !resource_size()] > [djiang: use the static mode name string array in mode_store()] > [Jonathan: remove rc check from mode to region index] > [Jonathan: clarify decoder mode 'mixed'] > [djbw: drop cleanup patch and just follow the convention in cxl_dpa_set_mode()] > [fan: make dcd resource size check similar to other partitions] > [djbw, jonathan, fan: remove mode range check from dc_mode_to_region_index] > [iweiny: push sysfs versions to 6.12] > --- > Documentation/ABI/testing/sysfs-bus-cxl | 21 ++++++++++---------- > drivers/cxl/core/hdm.c | 10 ++++++++++ > drivers/cxl/core/port.c | 10 +++++----- > drivers/cxl/cxl.h | 35 ++++++++++++++++++--------------- > 4 files changed, 45 insertions(+), 31 deletions(-) > > diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl > index 3f5627a1210a..957717264709 100644 > --- a/Documentation/ABI/testing/sysfs-bus-cxl > +++ b/Documentation/ABI/testing/sysfs-bus-cxl > @@ -316,23 +316,24 @@ Description: > > > What: /sys/bus/cxl/devices/decoderX.Y/mode > -Date: May, 2022 > -KernelVersion: v6.0 > +Date: May, 2022, October 2024 > +KernelVersion: v6.0, v6.12 (dcY) > Contact: linux-cxl@xxxxxxxxxxxxxxx > Description: > (RW) When a CXL decoder is of devtype "cxl_decoder_endpoint" it > translates from a host physical address range, to a device local > address range. Device-local address ranges are further split > - into a 'ram' (volatile memory) range and 'pmem' (persistent > - memory) range. The 'mode' attribute emits one of 'ram', 'pmem', > - 'mixed', or 'none'. The 'mixed' indication is for error cases > - when a decoder straddles the volatile/persistent partition > - boundary, and 'none' indicates the decoder is not actively > - decoding, or no DPA allocation policy has been set. > + into a 'ram' (volatile memory) range, 'pmem' (persistent > + memory) range, or Dynamic Capacity (DC) range. The 'mode' > + attribute emits one of 'ram', 'pmem', 'dcY', 'mixed', or > + 'none'. The 'mixed' indication is for error cases when a > + decoder straddles partition boundaries, and 'none' indicates > + the decoder is not actively decoding, or no DPA allocation > + policy has been set. > > 'mode' can be written, when the decoder is in the 'disabled' > - state, with either 'ram' or 'pmem' to set the boundaries for the > - next allocation. > + state, with 'ram', 'pmem', or 'dcY' to set the boundaries for > + the next allocation. > > > What: /sys/bus/cxl/devices/decoderX.Y/dpa_resource > diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c > index b4a517c6d283..ceca0b3d3e5c 100644 > --- a/drivers/cxl/core/hdm.c > +++ b/drivers/cxl/core/hdm.c > @@ -551,6 +551,7 @@ int cxl_dpa_set_mode(struct cxl_endpoint_decoder *cxled, > switch (mode) { > case CXL_DECODER_RAM: > case CXL_DECODER_PMEM: > + case CXL_DECODER_DC0 ... CXL_DECODER_DC7: > break; > default: > dev_dbg(dev, "unsupported mode: %d\n", mode); > @@ -578,6 +579,15 @@ int cxl_dpa_set_mode(struct cxl_endpoint_decoder *cxled, > goto out; > } > > + if (mode >= CXL_DECODER_DC0 && mode <= CXL_DECODER_DC7) { > + rc = dc_mode_to_region_index(mode); > + if (!resource_size(&cxlds->dc_res[rc])) { > + dev_dbg(dev, "no available dynamic capacity\n"); > + rc = -ENXIO; > + goto out; > + } > + } > + > cxled->mode = mode; > rc = 0; > out: > diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c > index 8054cbaac9f6..222aa0aeeef7 100644 > --- a/drivers/cxl/core/port.c > +++ b/drivers/cxl/core/port.c > @@ -205,11 +205,11 @@ static ssize_t mode_store(struct device *dev, struct device_attribute *attr, > enum cxl_decoder_mode mode; > ssize_t rc; > > - if (sysfs_streq(buf, "pmem")) > - mode = CXL_DECODER_PMEM; > - else if (sysfs_streq(buf, "ram")) > - mode = CXL_DECODER_RAM; > - else > + for (mode = CXL_DECODER_RAM; mode < CXL_DECODER_MIXED; mode++) > + if (sysfs_streq(buf, cxl_decoder_mode_names[mode])) > + break; > + > + if (mode >= CXL_DECODER_MIXED) > return -EINVAL; > > rc = cxl_dpa_set_mode(cxled, mode); > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h > index 53b666ef4097..16861c867537 100644 > --- a/drivers/cxl/cxl.h > +++ b/drivers/cxl/cxl.h > @@ -365,6 +365,9 @@ struct cxl_decoder { > /* > * CXL_DECODER_DEAD prevents endpoints from being reattached to regions > * while cxld_unregister() is running > + * > + * NOTE: CXL_DECODER_RAM must be second and CXL_DECODER_MIXED must be last. > + * See mode_store() > */ > enum cxl_decoder_mode { > CXL_DECODER_NONE, > @@ -382,25 +385,25 @@ enum cxl_decoder_mode { > CXL_DECODER_DEAD, > }; > > +static const char * const cxl_decoder_mode_names[] = { > + [CXL_DECODER_NONE] = "none", > + [CXL_DECODER_RAM] = "ram", > + [CXL_DECODER_PMEM] = "pmem", > + [CXL_DECODER_DC0] = "dc0", > + [CXL_DECODER_DC1] = "dc1", > + [CXL_DECODER_DC2] = "dc2", > + [CXL_DECODER_DC3] = "dc3", > + [CXL_DECODER_DC4] = "dc4", > + [CXL_DECODER_DC5] = "dc5", > + [CXL_DECODER_DC6] = "dc6", > + [CXL_DECODER_DC7] = "dc7", > + [CXL_DECODER_MIXED] = "mixed", > +}; > + > static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode) > { > - static const char * const names[] = { > - [CXL_DECODER_NONE] = "none", > - [CXL_DECODER_RAM] = "ram", > - [CXL_DECODER_PMEM] = "pmem", > - [CXL_DECODER_DC0] = "dc0", > - [CXL_DECODER_DC1] = "dc1", > - [CXL_DECODER_DC2] = "dc2", > - [CXL_DECODER_DC3] = "dc3", > - [CXL_DECODER_DC4] = "dc4", > - [CXL_DECODER_DC5] = "dc5", > - [CXL_DECODER_DC6] = "dc6", > - [CXL_DECODER_DC7] = "dc7", > - [CXL_DECODER_MIXED] = "mixed", > - }; > - > if (mode >= CXL_DECODER_NONE && mode <= CXL_DECODER_MIXED) > - return names[mode]; > + return cxl_decoder_mode_names[mode]; > return "mixed"; > } > >