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Diffstat (limited to 'drivers/cxl/core/trace.c')
-rw-r--r--drivers/cxl/core/trace.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/cxl/core/trace.c b/drivers/cxl/core/trace.c
index 29ae7ce81dc5..d0403dc3c8ab 100644
--- a/drivers/cxl/core/trace.c
+++ b/drivers/cxl/core/trace.c
@@ -1,5 +1,99 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2022 Intel Corporation. All rights reserved. */
+#include <cxl.h>
+#include "core.h"
+
#define CREATE_TRACE_POINTS
#include "trace.h"
+
+static bool cxl_is_hpa_in_range(u64 hpa, struct cxl_region *cxlr, int pos)
+{
+ struct cxl_region_params *p = &cxlr->params;
+ int gran = p->interleave_granularity;
+ int ways = p->interleave_ways;
+ u64 offset;
+
+ /* Is the hpa within this region at all */
+ if (hpa < p->res->start || hpa > p->res->end) {
+ dev_dbg(&cxlr->dev,
+ "Addr trans fail: hpa 0x%llx not in region\n", hpa);
+ return false;
+ }
+
+ /* Is the hpa in an expected chunk for its pos(-ition) */
+ offset = hpa - p->res->start;
+ offset = do_div(offset, gran * ways);
+ if ((offset >= pos * gran) && (offset < (pos + 1) * gran))
+ return true;
+
+ dev_dbg(&cxlr->dev,
+ "Addr trans fail: hpa 0x%llx not in expected chunk\n", hpa);
+
+ return false;
+}
+
+static u64 cxl_dpa_to_hpa(u64 dpa, struct cxl_region *cxlr,
+ struct cxl_endpoint_decoder *cxled)
+{
+ u64 dpa_offset, hpa_offset, bits_upper, mask_upper, hpa;
+ struct cxl_region_params *p = &cxlr->params;
+ int pos = cxled->pos;
+ u16 eig = 0;
+ u8 eiw = 0;
+
+ ways_to_eiw(p->interleave_ways, &eiw);
+ granularity_to_eig(p->interleave_granularity, &eig);
+
+ /*
+ * The device position in the region interleave set was removed
+ * from the offset at HPA->DPA translation. To reconstruct the
+ * HPA, place the 'pos' in the offset.
+ *
+ * The placement of 'pos' in the HPA is determined by interleave
+ * ways and granularity and is defined in the CXL Spec 3.0 Section
+ * 8.2.4.19.13 Implementation Note: Device Decode Logic
+ */
+
+ /* Remove the dpa base */
+ dpa_offset = dpa - cxl_dpa_resource_start(cxled);
+
+ mask_upper = GENMASK_ULL(51, eig + 8);
+
+ if (eiw < 8) {
+ hpa_offset = (dpa_offset & mask_upper) << eiw;
+ hpa_offset |= pos << (eig + 8);
+ } else {
+ bits_upper = (dpa_offset & mask_upper) >> (eig + 8);
+ bits_upper = bits_upper * 3;
+ hpa_offset = ((bits_upper << (eiw - 8)) + pos) << (eig + 8);
+ }
+
+ /* The lower bits remain unchanged */
+ hpa_offset |= dpa_offset & GENMASK_ULL(eig + 7, 0);
+
+ /* Apply the hpa_offset to the region base address */
+ hpa = hpa_offset + p->res->start;
+
+ if (!cxl_is_hpa_in_range(hpa, cxlr, cxled->pos))
+ return ULLONG_MAX;
+
+ return hpa;
+}
+
+u64 cxl_trace_hpa(struct cxl_region *cxlr, struct cxl_memdev *cxlmd,
+ u64 dpa)
+{
+ struct cxl_region_params *p = &cxlr->params;
+ struct cxl_endpoint_decoder *cxled = NULL;
+
+ for (int i = 0; i < p->nr_targets; i++) {
+ cxled = p->targets[i];
+ if (cxlmd == cxled_to_memdev(cxled))
+ break;
+ }
+ if (!cxled || cxlmd != cxled_to_memdev(cxled))
+ return ULLONG_MAX;
+
+ return cxl_dpa_to_hpa(dpa, cxlr, cxled);
+}