Commit 85afc317 authored by Ben Widawsky's avatar Ben Widawsky Committed by Dan Williams
Browse files

cxl/pci: Split cxl_pci_setup_regs() 



In preparation for moving parts of register mapping to cxl_core, split
cxl_pci_setup_regs() into a helper that finds register blocks,
(cxl_find_regblock()), and a generic wrapper that probes the precise
register sets within a block (cxl_setup_regs()).

Move the actual mapping (cxl_map_regs()) of the only register-set that
cxl_pci cares about (memory device registers) up a level from the former
cxl_pci_setup_regs() into cxl_pci_probe().

With this change the unused component registers are no longer mapped,
but the helpers are primed to move into the core.

[djbw: drop cxl_map_regs() for component registers]

Signed-off-by: default avatarBen Widawsky <ben.widawsky@intel.com>
[djbw: rebase on the cxl_register_map refactor]
Reviewed-by: default avatarIra Weiny <ira.weiny@intel.com>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163434053788.914258.18412599112859205220.stgit@dwillia2-desk3.amr.corp.intel.com


Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent a261e9a1

drivers/cxl/pci.c

+37 −36
Original line number Diff line number Diff line
@@ -433,72 +433,69 @@ static void cxl_decode_regblock(u32 reg_lo, u32 reg_hi, 
}



/**

 * cxl_pci_setup_regs() - Setup necessary MMIO.

 * @cxlm: The CXL memory device to communicate with.

 * cxl_find_regblock() - Locate register blocks by type

 * @pdev: The CXL PCI device to enumerate.

 * @type: Register Block Indicator id

 * @map: Enumeration output, clobbered on error

 *

 * Return: 0 if all necessary registers mapped.

 * Return: 0 if register block enumerated, negative error code otherwise

 *

 * A memory device is required by spec to implement a certain set of MMIO

 * regions. The purpose of this function is to enumerate and map those

 * registers.

 * A CXL DVSEC may point to one or more register blocks, search for them

 * by @type.

 */

static int cxl_pci_setup_regs(struct cxl_mem *cxlm)

static int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,

			     struct cxl_register_map *map)

{

	u32 regloc_size, regblocks;

	int regloc, i, n_maps, ret = 0;

	struct device *dev = cxlm->dev;

	struct pci_dev *pdev = to_pci_dev(dev);

	struct cxl_register_map *map, maps[CXL_REGLOC_RBI_TYPES];

	int regloc, i;



	regloc = cxl_pci_dvsec(pdev, PCI_DVSEC_ID_CXL_REGLOC_DVSEC_ID);

	if (!regloc) {

		dev_err(dev, "register location dvsec not found\n");

	if (!regloc)

		return -ENXIO;

	}



	/* Get the size of the Register Locator DVSEC */

	pci_read_config_dword(pdev, regloc + PCI_DVSEC_HEADER1, &regloc_size);

	regloc_size = FIELD_GET(PCI_DVSEC_HEADER1_LENGTH_MASK, regloc_size);



	regloc += PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET;

	regblocks = (regloc_size - PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET) / 8;



	for (i = 0, n_maps = 0; i < regblocks; i++, regloc += 8) {

	for (i = 0; i < regblocks; i++, regloc += 8) {

		u32 reg_lo, reg_hi;



		pci_read_config_dword(pdev, regloc, &reg_lo);

		pci_read_config_dword(pdev, regloc + 4, &reg_hi);



		map = &maps[n_maps];

		cxl_decode_regblock(reg_lo, reg_hi, map);



		/* Ignore unknown register block types */

		if (map->reg_type > CXL_REGLOC_RBI_MEMDEV)

			continue;

		if (map->reg_type == type)

			return 0;

	}



		ret = cxl_map_regblock(pdev, map);

		if (ret)

			return ret;

	return -ENODEV;

}



		ret = cxl_probe_regs(pdev, map);

		cxl_unmap_regblock(pdev, map);

		if (ret)

			return ret;

static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,

			  struct cxl_register_map *map)

{

	int rc;



		n_maps++;

	}

	rc = cxl_find_regblock(pdev, type, map);

	if (rc)

		return rc;



	for (i = 0; i < n_maps; i++) {

		ret = cxl_map_regs(cxlm, &maps[i]);

		if (ret)

			break;

	}

	rc = cxl_map_regblock(pdev, map);

	if (rc)

		return rc;



	return ret;

	rc = cxl_probe_regs(pdev, map);

	cxl_unmap_regblock(pdev, map);



	return rc;

}



static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)

{

	struct cxl_register_map map;

	struct cxl_memdev *cxlmd;

	struct cxl_mem *cxlm;

	int rc;
@@ -518,7 +515,11 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) 
	if (IS_ERR(cxlm))

		return PTR_ERR(cxlm);



	rc = cxl_pci_setup_regs(cxlm);

	rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map);

	if (rc)

		return rc;



	rc = cxl_map_regs(cxlm, &map);

	if (rc)

		return rc;