| Message ID | 167588394236.1155956.8466475582138210344.stgit@djiang5-mobl3.local |
|---|---|
| Headers | show |
| Series | cxl: Introduce HDM decoder emulation from DVSEC range registers | expand |
Dave Jiang wrote: > v4: > - Init invalid range start to 0. (Dan) > - Direct assign range to range. (Dan) > - Add comment for why emulated decoder is locked. (Dan) > - Check range_len() instead of content of .start. (Dan) > - Fix too long line formatting. (Dan) > - Remove ->emulate_decoders (Dan) > - Dropped v3 7/8 patch. (Dan) > - Change decoder lock removal commit log for more clarity. (Dan) > > v3: > - Simplify to directly return devm_cxl_enable_mem() in > cxl_hdm_decode_init(). (Jonathan) > - Move relevant changes from 6/8 to 5/8 and update kdoc. (Jonathan) > - Add kernel doc update. (Jonathan) > > v2: > - Refactor to continue when size is 0. (Jonathan) > - Update kdoc comments (Jonathan) > - Use a bool for is_cxl_endpoint() to make it easier for static analysis > (Jonathan) > - Update commit log to indicate cxl_hdm_decode_init() return additional > error codes after change. (Jonathan) > - Set target_type to CXL_DECODER_EXPANDER (type 3). (Jonathan) > - Skip HDM enabling if DVSEC range is active. (Jonathan) > - Set target_count to same as number of ranges. (Jonathan) > - Set target_type to CXL_DECODER_EXPANDER (type 3). (Jonathan) > - Refactor to put error case out of line. (Jonathan) > - Drop 7/8 "cxl: suppress component register discovery failure warning for RCD" > - Add support for missing case where HDM decoders are present but no decoders > are committed. (Case 5 below) > > This series provides the emulation of HDM decoders from the programmed range > registers. From CXL 3.0 spec 8.1.3.8, there can be up to 2 ranges programmed. > Some devices may not implement HDM decoder registers and some may not be > programmed by the BIOS. Under such scenarios, if one of more range registers > are programmed, then we can create an emulated HDM decoder per active range > indicated by the range registers. The emulated HDM decoders will show up as > locked and cannot be reprogrammed. > > Below is a table that indicates different scenarios the driver may encounter: > > rr: Range registers not programmed > hdm: HDM decoders not programmed > RR: Range registers programmed by BIOS > HDM: HDM decoders programmed by BIOS > > emulate HDM: Create HDM decoder software structs and use values from range registers. > keep HDM: Populate HDM decoder software structs with values in HDM decoder registers. > > Case 1: Case 2: Case 3: Case 4: Case 5: Case 6: > rr RR rr hdm rr HDM RR hdm RR HDM > unsupported emulate HDM keep HDM keep HDM emulate HDM keep HDM > > For convenience, the kernel branch can be retrieved here [1]. > > [1]: https://git.kernel.org/pub/scm/linux/kernel/git/djiang/linux.git/log/?h=cxl-emulate-hdm > > base-commit: 4ec5183ec48656cec489c49f989c508b68b518e3 > > --- > > Dave Jiang (7): > cxl: break out range register decoding from cxl_hdm_decode_init() > cxl: export cxl_dvsec_rr_decode() to cxl_port > cxl: refactor cxl_hdm_decode_init() > cxl: emulate HDM decoder from DVSEC range registers > cxl: create emulated cxl_hdm for devices that do not have HDM decoders > cxl: Add emulation when HDM decoders are not committed > cxl: remove locked check for dvsec_range_allowed() > > > drivers/cxl/core/hdm.c | 119 +++++++++++++++++++++--- > drivers/cxl/core/pci.c | 199 +++++++++++++++++++---------------------- > drivers/cxl/cxl.h | 20 ++++- > drivers/cxl/cxlmem.h | 12 --- > drivers/cxl/cxlpci.h | 3 +- > drivers/cxl/port.c | 25 ++++-- > 6 files changed, 237 insertions(+), 141 deletions(-) Oh, this all looks good on the base driver, but this missed updating cxl_test: tools/testing/cxl/test/mock.c: In function ‘__wrap_devm_cxl_setup_hdm’: tools/testing/cxl/test/mock.c:143:26: error: too few arguments to function ‘devm_cxl_setup_hdm’ 143 | cxlhdm = devm_cxl_setup_hdm(port); | ^~~~~~~~~~~~~~~~~~ In file included from ./drivers/cxl/cxlmem.h:8, from tools/testing/cxl/test/mock.c:10: ./drivers/cxl/cxl.h:664:17: note: declared here 664 | struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port, | ^~~~~~~~~~~~~~~~~~ tools/testing/cxl/test/mock.c: In function ‘__wrap_devm_cxl_enumerate_decoders’: tools/testing/cxl/test/mock.c:174:22: error: too few arguments to function ‘devm_cxl_enumerate_decoders’ 174 | rc = devm_cxl_enumerate_decoders(cxlhdm); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ ./drivers/cxl/cxl.h:666:5: note: declared here 666 | int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ tools/testing/cxl/test/mock.c: In function ‘__wrap_cxl_hdm_decode_init’: tools/testing/cxl/test/mock.c:220:22: error: too few arguments to function ‘cxl_hdm_decode_init’ 220 | rc = cxl_hdm_decode_init(cxlds, cxlhdm); | ^~~~~~~~~~~~~~~~~~~ In file included from tools/testing/cxl/test/mock.c:11: ./drivers/cxl/cxlpci.h:73:5: note: declared here 73 | int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm, | ^~~~~~~~~~~~~~~~~~~
v4: - Init invalid range start to 0. (Dan) - Direct assign range to range. (Dan) - Add comment for why emulated decoder is locked. (Dan) - Check range_len() instead of content of .start. (Dan) - Fix too long line formatting. (Dan) - Remove ->emulate_decoders (Dan) - Dropped v3 7/8 patch. (Dan) - Change decoder lock removal commit log for more clarity. (Dan) v3: - Simplify to directly return devm_cxl_enable_mem() in cxl_hdm_decode_init(). (Jonathan) - Move relevant changes from 6/8 to 5/8 and update kdoc. (Jonathan) - Add kernel doc update. (Jonathan) v2: - Refactor to continue when size is 0. (Jonathan) - Update kdoc comments (Jonathan) - Use a bool for is_cxl_endpoint() to make it easier for static analysis (Jonathan) - Update commit log to indicate cxl_hdm_decode_init() return additional error codes after change. (Jonathan) - Set target_type to CXL_DECODER_EXPANDER (type 3). (Jonathan) - Skip HDM enabling if DVSEC range is active. (Jonathan) - Set target_count to same as number of ranges. (Jonathan) - Set target_type to CXL_DECODER_EXPANDER (type 3). (Jonathan) - Refactor to put error case out of line. (Jonathan) - Drop 7/8 "cxl: suppress component register discovery failure warning for RCD" - Add support for missing case where HDM decoders are present but no decoders are committed. (Case 5 below) This series provides the emulation of HDM decoders from the programmed range registers. From CXL 3.0 spec 8.1.3.8, there can be up to 2 ranges programmed. Some devices may not implement HDM decoder registers and some may not be programmed by the BIOS. Under such scenarios, if one of more range registers are programmed, then we can create an emulated HDM decoder per active range indicated by the range registers. The emulated HDM decoders will show up as locked and cannot be reprogrammed. Below is a table that indicates different scenarios the driver may encounter: rr: Range registers not programmed hdm: HDM decoders not programmed RR: Range registers programmed by BIOS HDM: HDM decoders programmed by BIOS emulate HDM: Create HDM decoder software structs and use values from range registers. keep HDM: Populate HDM decoder software structs with values in HDM decoder registers. Case 1: Case 2: Case 3: Case 4: Case 5: Case 6: rr RR rr hdm rr HDM RR hdm RR HDM unsupported emulate HDM keep HDM keep HDM emulate HDM keep HDM For convenience, the kernel branch can be retrieved here [1]. [1]: https://git.kernel.org/pub/scm/linux/kernel/git/djiang/linux.git/log/?h=cxl-emulate-hdm base-commit: 4ec5183ec48656cec489c49f989c508b68b518e3 --- Dave Jiang (7): cxl: break out range register decoding from cxl_hdm_decode_init() cxl: export cxl_dvsec_rr_decode() to cxl_port cxl: refactor cxl_hdm_decode_init() cxl: emulate HDM decoder from DVSEC range registers cxl: create emulated cxl_hdm for devices that do not have HDM decoders cxl: Add emulation when HDM decoders are not committed cxl: remove locked check for dvsec_range_allowed() drivers/cxl/core/hdm.c | 119 +++++++++++++++++++++--- drivers/cxl/core/pci.c | 199 +++++++++++++++++++---------------------- drivers/cxl/cxl.h | 20 ++++- drivers/cxl/cxlmem.h | 12 --- drivers/cxl/cxlpci.h | 3 +- drivers/cxl/port.c | 25 ++++-- 6 files changed, 237 insertions(+), 141 deletions(-) --