On Wed, Mar 22, 2023 at 10:33:00AM +0000, Jonathan Cameron wrote: > The hardware clearing the commit bit is not spec compliant. > Clearing of committed bit when commit is cleared is not specifically > stated in the CXL spec, but is the expected (and simplest) permitted > behaviour so use that for QEMU emulation. > > Signed-off-by: Jonathan Cameron <jonathan.came...@huawei.com> > ---
Reviewed-by: Fan Ni <fan...@samsung.com> Tested-by: Fan Ni <fan...@samsung.com> The patch passed the tests as shown in previous mailing list discussion: https://lore.kernel.org/linux-cxl/640276695c8e8_5b27929...@dwillia2-xfh.jf.intel.com.notmuch/T/#m0afcfc21d68c84c07f2e9e3194f587c2ffa82d6d The following two topologies are tested: 1. one HB with one root port and a direct attached memdev. 2. one HB with 2 root ports and a memdev is directly attached to a CXL switch which is attached to one root port. One minor thing below. > hw/cxl/cxl-component-utils.c | 6 +++++- > hw/mem/cxl_type3.c | 21 ++++++++++++++++++++- > 2 files changed, 25 insertions(+), 2 deletions(-) > > diff --git a/hw/cxl/cxl-component-utils.c b/hw/cxl/cxl-component-utils.c > index a3e6cf75cf..378f1082ce 100644 > --- a/hw/cxl/cxl-component-utils.c > +++ b/hw/cxl/cxl-component-utils.c > @@ -38,19 +38,23 @@ static void dumb_hdm_handler(CXLComponentState > *cxl_cstate, hwaddr offset, > ComponentRegisters *cregs = &cxl_cstate->crb; > uint32_t *cache_mem = cregs->cache_mem_registers; > bool should_commit = false; > + bool should_uncommit = false; > > switch (offset) { > case A_CXL_HDM_DECODER0_CTRL: > should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT); > + should_uncommit = !should_commit; This will cause committed always reset if COMMIT is 0, not only 1->0. No issue for now, just point out to make sure it is what we want. > break; > default: > break; > } > > if (should_commit) { > - value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, COMMIT, 0); > value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, ERR, 0); > value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, COMMITTED, 1); > + } else if (should_uncommit) { > + value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, ERR, 0); > + value = FIELD_DP32(value, CXL_HDM_DECODER0_CTRL, COMMITTED, 0); > } > stl_le_p((uint8_t *)cache_mem + offset, value); > } > diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c > index 846089ccda..9598d584ac 100644 > --- a/hw/mem/cxl_type3.c > +++ b/hw/mem/cxl_type3.c > @@ -320,13 +320,28 @@ static void hdm_decoder_commit(CXLType3Dev *ct3d, int > which) > > ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL); > /* TODO: Sanity checks that the decoder is possible */ > - ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, COMMIT, 0); > ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, ERR, 0); > ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED, 1); > > stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL, ctrl); > } > > +static void hdm_decoder_uncommit(CXLType3Dev *ct3d, int which) > +{ > + ComponentRegisters *cregs = &ct3d->cxl_cstate.crb; > + uint32_t *cache_mem = cregs->cache_mem_registers; > + uint32_t ctrl; > + > + assert(which == 0); > + > + ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL); > + > + ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, ERR, 0); > + ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED, 0); > + > + stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL, ctrl); > +} > + > static int ct3d_qmp_uncor_err_to_cxl(CxlUncorErrorType qmp_err) > { > switch (qmp_err) { > @@ -395,6 +410,7 @@ static void ct3d_reg_write(void *opaque, hwaddr offset, > uint64_t value, > CXLType3Dev *ct3d = container_of(cxl_cstate, CXLType3Dev, cxl_cstate); > uint32_t *cache_mem = cregs->cache_mem_registers; > bool should_commit = false; > + bool should_uncommit = false; > int which_hdm = -1; > > assert(size == 4); > @@ -403,6 +419,7 @@ static void ct3d_reg_write(void *opaque, hwaddr offset, > uint64_t value, > switch (offset) { > case A_CXL_HDM_DECODER0_CTRL: > should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT); > + should_uncommit = !should_commit; > which_hdm = 0; > break; > case A_CXL_RAS_UNC_ERR_STATUS: > @@ -489,6 +506,8 @@ static void ct3d_reg_write(void *opaque, hwaddr offset, > uint64_t value, > stl_le_p((uint8_t *)cache_mem + offset, value); > if (should_commit) { > hdm_decoder_commit(ct3d, which_hdm); > + } else if (should_uncommit) { > + hdm_decoder_uncommit(ct3d, which_hdm); > } > } > > -- > 2.37.2 >
