On 3/28/23 5:44 PM, Alison Schofield wrote:
On Mon, Mar 27, 2023 at 02:44:39PM -0700, Dave Jiang wrote:
Provide a callback to parse the Device Scoped Latency and Bandwidth
Information Structure (DSLBIS) in the CDAT structures. The DSLBIS
contains the bandwidth and latency information that's tied to a DSMAS
handle. The driver will retrieve the read and write latency and
bandwidth associated with the DSMAS which is tied to a DPA range.
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
---
v2:
- Add size check to DSLIBIS table. (Lukas)
- Remove unnecessary entry type check. (Jonathan)
- Move data_type check to after match. (Jonathan)
- Skip unknown data type. (Jonathan)
- Add overflow check for unit multiply. (Jonathan)
- Use dev_warn() when entries parsing fail. (Jonathan)
---
drivers/cxl/core/cdat.c | 41 +++++++++++++++++++++++++++++++++++++++++
drivers/cxl/cxlpci.h | 34 +++++++++++++++++++++++++++++++++-
drivers/cxl/port.c | 9 ++++++++-
3 files changed, 82 insertions(+), 2 deletions(-)
diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c
index d068609fb6f9..0e88973e9f38 100644
--- a/drivers/cxl/core/cdat.c
+++ b/drivers/cxl/core/cdat.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2023 Intel Corporation. All rights reserved. */
+#include <linux/overflow.h>
#include "cxlpci.h"
#include "cxl.h"
@@ -124,3 +125,43 @@ int cxl_dsmas_parse_entry(struct cdat_entry_header *header, void *arg)
return 0;
}
EXPORT_SYMBOL_NS_GPL(cxl_dsmas_parse_entry, CXL);
+
+int cxl_dslbis_parse_entry(struct cdat_entry_header *header, void *arg)
+{
+ struct cdat_dslbis *dslbis = (struct cdat_dslbis *)header;
+ struct list_head *dsmas_list = (struct list_head *)arg;
cast from void ?
ok
+ struct dsmas_entry *dent;
+
+ if (dslbis->hdr.length != sizeof(*dslbis)) {
+ pr_warn("Malformed DSLBIS table length: (%lu:%u)\n",
+ (unsigned long)sizeof(*dslbis), dslbis->hdr.length);
+ return -EINVAL;
+ }
+
+ /* Unrecognized data type, we can skip */
/* Skip unrecognized data type */
ok
+ if (dslbis->data_type >= HMAT_SLLBIS_DATA_TYPE_MAX)
+ return 0;
+
+ list_for_each_entry(dent, dsmas_list, list) {
+ u64 val;
+ int rc;
+
+ if (dslbis->handle != dent->handle)
+ continue;
+
+ /* Not a memory type, skip */
+ if ((dslbis->flags & DSLBIS_MEM_MASK) != DSLBIS_MEM_MEMORY)
+ return 0;
+
+ rc = check_mul_overflow(le64_to_cpu(dslbis->entry_base_unit),
+ le16_to_cpu(dslbis->entry[0]), &val);
+ if (unlikely(rc))
+ pr_warn("DSLBIS value overflowed!\n");
Must this be shouted !
I have a vague recollection of being told not to use exclamation points
in user visible messages.
ok
+
+ dent->qos[dslbis->data_type] = val;
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_dslbis_parse_entry, CXL);
diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
index 9a2468a93d83..1429de49e0c4 100644
--- a/drivers/cxl/cxlpci.h
+++ b/drivers/cxl/cxlpci.h
@@ -104,10 +104,21 @@ struct cdat_subtable_entry {
enum cdat_type type;
};
+enum {
+ HMAT_SLLBIS_ACCESS_LATENCY = 0,
+ HMAT_SLLBIS_READ_LATENCY,
+ HMAT_SLLBIS_WRITE_LATENCY,
+ HMAT_SLLBIS_ACCESS_BANDWIDTH,
+ HMAT_SLLBIS_READ_BANDWIDTH,
+ HMAT_SLLBIS_WRITE_BANDWIDTH,
+ HMAT_SLLBIS_DATA_TYPE_MAX
+};
+
struct dsmas_entry {
struct list_head list;
struct range dpa_range;
u8 handle;
+ u64 qos[HMAT_SLLBIS_DATA_TYPE_MAX];
};
/* Sub-table 0: Device Scoped Memory Affinity Structure (DSMAS) */
@@ -120,6 +131,23 @@ struct cdat_dsmas {
__le64 dpa_length;
} __packed;
+/* Sub-table 1: Device Scoped Latency and Bandwidth Information Structure (DSLBIS) */
+struct cdat_dslbis {
+ struct cdat_entry_header hdr;
+ u8 handle;
+ u8 flags;
+ u8 data_type;
+ u8 reserved;
+ __le64 entry_base_unit;
+ __le16 entry[3];
+ __le16 reserved2;
+} __packed;
+
+/* Flags for subtable above */
/* Flags for DSLBIS subtable */
ok
+
+#define DSLBIS_MEM_MASK GENMASK(3, 0)
+#define DSLBIS_MEM_MEMORY 0
+
int devm_cxl_port_enumerate_dports(struct cxl_port *port);
struct cxl_dev_state;
int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm,
@@ -136,5 +164,9 @@ cdat_table_parse(dsmas);
cdat_table_parse(dslbis);
cdat_table_parse(sslbis);
-int cxl_dsmas_parse_entry(struct cdat_entry_header *header, void *arg);
+#define cxl_parse_entry(x) \
+int cxl_##x##_parse_entry(struct cdat_entry_header *header, void *arg)
+
+cxl_parse_entry(dsmas);
+cxl_parse_entry(dslbis);
#endif /* __CXL_PCI_H__ */
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index c8136797d528..6f2b327f7128 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -152,8 +152,15 @@ static int cxl_port_probe(struct device *dev)
rc = cdat_table_parse_dsmas(port->cdat.table,
cxl_dsmas_parse_entry,
(void *)&dsmas_list);
- if (rc < 0)
+ if (rc > 0) {
+ rc = cdat_table_parse_dslbis(port->cdat.table,
+ cxl_dslbis_parse_entry,
+ (void *)&dsmas_list);
+ if (rc <= 0)
+ dev_warn(dev, "Failed to parse DSLBIS: %d\n", rc);
+ } else {
dev_warn(dev, "Failed to parse DSMAS: %d\n", rc);
+ }
I see you touch this func more than once. Maybe some earlier nips and
tucks, makes this more readable.
Not sure what you mean.
dsmas_list_destroy(&dsmas_list);
}
