Commit 6697b2cf authored by Dan Williams's avatar Dan Williams
Browse files

nfit: fix multi-interface dimm handling, acpi6.1 compatibility 



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.
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
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: <stable@vger.kernel.org>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 18558cae

drivers/acpi/nfit.c

+35 −36
Original line number Diff line number Diff line
@@ -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;

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