On 2/8/2016 2:10 PM, Linda Knippers wrote: > On 2/8/2016 1:30 PM, Dan Williams wrote: >> ACPI 6.1 clarified that multi-interface dimms require multiple control >> region entries (DCRs) per dimm. Previously we were assuming that a >> control region is only present when block-data-windows are present. > > We need to give this a quick test with NVDIMM-N because those types of > NVDIMMs have control regions without block-data-windows. We've fixed > bugs related to that assumption a couple of times.
I can't test the conditions for which these changes were made but the code continues to work on my NVDIMM-N system where we have control regions w/o block-data windows. -- ljk > >> This implementation was done with an eye to be compatibility with the >> looser ACPI 6.0 interpretation of this table. >> >> 1/ When coalescing the memory device (MEMDEV) tables for a single dimm, >> coalesce on device_handle rather than control region index. >> >> 2/ Whenever we disocver a control region with non-zero block windows > discover > >> re-scan for block-data-window (BDW) entries. >> >> We may need to revisit this if a DIMM ever implements a format interface >> outside of blk or pmem, but that is not on the foreseeable horizon. >> >> Cc: <[email protected]> >> Signed-off-by: Dan Williams <[email protected]> >> --- >> drivers/acpi/nfit.c | 71 >> +++++++++++++++++++++++++-------------------------- >> 1 file changed, 35 insertions(+), 36 deletions(-) >> >> diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c >> index ad6d8c6b777e..424b362e8fdc 100644 >> --- a/drivers/acpi/nfit.c >> +++ b/drivers/acpi/nfit.c >> @@ -469,37 +469,16 @@ static void nfit_mem_find_spa_bdw(struct >> acpi_nfit_desc *acpi_desc, >> nfit_mem->bdw = NULL; >> } >> >> -static int nfit_mem_add(struct acpi_nfit_desc *acpi_desc, >> +static void nfit_mem_init_bdw(struct acpi_nfit_desc *acpi_desc, >> struct nfit_mem *nfit_mem, struct acpi_nfit_system_address *spa) >> { >> u16 dcr = __to_nfit_memdev(nfit_mem)->region_index; >> struct nfit_memdev *nfit_memdev; >> struct nfit_flush *nfit_flush; >> - struct nfit_dcr *nfit_dcr; >> struct nfit_bdw *nfit_bdw; >> struct nfit_idt *nfit_idt; >> u16 idt_idx, range_index; >> >> - list_for_each_entry(nfit_dcr, &acpi_desc->dcrs, list) { >> - if (nfit_dcr->dcr->region_index != dcr) >> - continue; >> - nfit_mem->dcr = nfit_dcr->dcr; >> - break; >> - } >> - >> - if (!nfit_mem->dcr) { >> - dev_dbg(acpi_desc->dev, "SPA %d missing:%s%s\n", >> - spa->range_index, __to_nfit_memdev(nfit_mem) >> - ? "" : " MEMDEV", nfit_mem->dcr ? "" : " DCR"); >> - return -ENODEV; >> - } >> - >> - /* >> - * We've found enough to create an nvdimm, optionally >> - * find an associated BDW >> - */ >> - list_add(&nfit_mem->list, &acpi_desc->dimms); >> - >> list_for_each_entry(nfit_bdw, &acpi_desc->bdws, list) { >> if (nfit_bdw->bdw->region_index != dcr) >> continue; >> @@ -508,12 +487,12 @@ static int nfit_mem_add(struct acpi_nfit_desc >> *acpi_desc, >> } >> >> if (!nfit_mem->bdw) >> - return 0; >> + return; >> >> nfit_mem_find_spa_bdw(acpi_desc, nfit_mem); >> >> if (!nfit_mem->spa_bdw) >> - return 0; >> + return; >> >> range_index = nfit_mem->spa_bdw->range_index; >> list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) { >> @@ -538,8 +517,6 @@ static int nfit_mem_add(struct acpi_nfit_desc *acpi_desc, >> } >> break; >> } >> - >> - return 0; >> } >> >> static int nfit_mem_dcr_init(struct acpi_nfit_desc *acpi_desc, >> @@ -548,7 +525,6 @@ static int nfit_mem_dcr_init(struct acpi_nfit_desc >> *acpi_desc, >> struct nfit_mem *nfit_mem, *found; >> struct nfit_memdev *nfit_memdev; >> int type = nfit_spa_type(spa); >> - u16 dcr; >> >> switch (type) { >> case NFIT_SPA_DCR: >> @@ -559,14 +535,18 @@ static int nfit_mem_dcr_init(struct acpi_nfit_desc >> *acpi_desc, >> } >> >> list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) { >> - int rc; >> + struct nfit_dcr *nfit_dcr; >> + u32 device_handle; >> + u16 dcr; >> >> if (nfit_memdev->memdev->range_index != spa->range_index) >> continue; >> found = NULL; >> dcr = nfit_memdev->memdev->region_index; >> + device_handle = nfit_memdev->memdev->device_handle; >> list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) >> - if (__to_nfit_memdev(nfit_mem)->region_index == dcr) { >> + if (__to_nfit_memdev(nfit_mem)->device_handle >> + == device_handle) { >> found = nfit_mem; >> break; >> } >> @@ -579,6 +559,31 @@ static int nfit_mem_dcr_init(struct acpi_nfit_desc >> *acpi_desc, >> if (!nfit_mem) >> return -ENOMEM; >> INIT_LIST_HEAD(&nfit_mem->list); >> + list_add(&nfit_mem->list, &acpi_desc->dimms); >> + } >> + >> + list_for_each_entry(nfit_dcr, &acpi_desc->dcrs, list) { >> + if (nfit_dcr->dcr->region_index != dcr) >> + continue; >> + /* >> + * Record the control region for the dimm. For >> + * the ACPI 6.1 case, where there are separate >> + * control regions for the pmem vs blk >> + * interfaces, be sure to record the extended >> + * blk details. >> + */ >> + if (!nfit_mem->dcr) >> + nfit_mem->dcr = nfit_dcr->dcr; >> + else if (nfit_mem->dcr->windows == 0 >> + && nfit_dcr->dcr->windows) >> + nfit_mem->dcr = nfit_dcr->dcr; >> + break; >> + } >> + >> + if (dcr && !nfit_mem->dcr) { >> + dev_err(acpi_desc->dev, "SPA %d missing DCR %d\n", >> + spa->range_index, dcr); >> + return -ENODEV; >> } >> >> if (type == NFIT_SPA_DCR) { >> @@ -595,6 +600,7 @@ static int nfit_mem_dcr_init(struct acpi_nfit_desc >> *acpi_desc, >> nfit_mem->idt_dcr = nfit_idt->idt; >> break; >> } >> + nfit_mem_init_bdw(acpi_desc, nfit_mem, spa); >> } else { >> /* >> * A single dimm may belong to multiple SPA-PM >> @@ -603,13 +609,6 @@ static int nfit_mem_dcr_init(struct acpi_nfit_desc >> *acpi_desc, >> */ >> nfit_mem->memdev_pmem = nfit_memdev->memdev; >> } >> - >> - if (found) >> - continue; >> - >> - rc = nfit_mem_add(acpi_desc, nfit_mem, spa); >> - if (rc) >> - return rc; >> } >> >> return 0; >> >> _______________________________________________ >> Linux-nvdimm mailing list >> [email protected] >> https://lists.01.org/mailman/listinfo/linux-nvdimm >>
