diff options
| author | Yao Xingtao <yaoxt.fnst@fujitsu.com> | 2024-06-14 11:47:54 +0300 |
|---|---|---|
| committer | Dave Jiang <dave.jiang@intel.com> | 2024-06-26 00:45:27 +0300 |
| commit | 84328c5acebc10c8cdcf17283ab6c6d548885bfc (patch) | |
| tree | 2c1bfd5acceec1334de5c0f116bbc612a9391ada /drivers/cxl/core/hdm.c | |
| parent | 285f2a08841432fc3e498b1cd00cce5216cdf189 (diff) | |
| download | linux-84328c5acebc10c8cdcf17283ab6c6d548885bfc.tar.xz | |
cxl/region: check interleave capability
Since interleave capability is not verified, if the interleave
capability of a target does not match the region need, committing decoder
should have failed at the device end.
In order to checkout this error as quickly as possible, driver needs
to check the interleave capability of target during attaching it to
region.
Per CXL specification r3.1(8.2.4.20.1 CXL HDM Decoder Capability Register),
bits 11 and 12 indicate the capability to establish interleaving in 3, 6,
12 and 16 ways. If these bits are not set, the target cannot be attached to
a region utilizing such interleave ways.
Additionally, bits 8 and 9 represent the capability of the bits used for
interleaving in the address, Linux tracks this in the cxl_port
interleave_mask.
Per CXL specification r3.1(8.2.4.20.13 Decoder Protection):
eIW means encoded Interleave Ways.
eIG means encoded Interleave Granularity.
in HPA:
if eIW is 0 or 8 (interleave ways: 1, 3), all the bits of HPA are used,
the interleave bits are none, the following check is ignored.
if eIW is less than 8 (interleave ways: 2, 4, 8, 16), the interleave bits
start at bit position eIG + 8 and end at eIG + eIW + 8 - 1.
if eIW is greater than 8 (interleave ways: 6, 12), the interleave bits
start at bit position eIG + 8 and end at eIG + eIW - 1.
if the interleave mask is insufficient to cover the required interleave
bits, the target cannot be attached to the region.
Fixes: 384e624bb211 ("cxl/region: Attach endpoint decoders")
Signed-off-by: Yao Xingtao <yaoxt.fnst@fujitsu.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://patch.msgid.link/20240614084755.59503-2-yaoxt.fnst@fujitsu.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Diffstat (limited to 'drivers/cxl/core/hdm.c')
| -rw-r--r-- | drivers/cxl/core/hdm.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c index 784843fa2a22..3df10517a327 100644 --- a/drivers/cxl/core/hdm.c +++ b/drivers/cxl/core/hdm.c @@ -52,6 +52,14 @@ int devm_cxl_add_passthrough_decoder(struct cxl_port *port) struct cxl_dport *dport = NULL; int single_port_map[1]; unsigned long index; + struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev); + + /* + * Capability checks are moot for passthrough decoders, support + * any and all possibilities. + */ + cxlhdm->interleave_mask = ~0U; + cxlhdm->iw_cap_mask = ~0UL; cxlsd = cxl_switch_decoder_alloc(port, 1); if (IS_ERR(cxlsd)) @@ -79,6 +87,11 @@ static void parse_hdm_decoder_caps(struct cxl_hdm *cxlhdm) cxlhdm->interleave_mask |= GENMASK(11, 8); if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_14_12, hdm_cap)) cxlhdm->interleave_mask |= GENMASK(14, 12); + cxlhdm->iw_cap_mask = BIT(1) | BIT(2) | BIT(4) | BIT(8); + if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_3_6_12_WAY, hdm_cap)) + cxlhdm->iw_cap_mask |= BIT(3) | BIT(6) | BIT(12); + if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_16_WAY, hdm_cap)) + cxlhdm->iw_cap_mask |= BIT(16); } static bool should_emulate_decoders(struct cxl_endpoint_dvsec_info *info) |