@@ -61,6 +61,7 @@ struct arm_smmu_entry_writer_ops {
#define NUM_ENTRY_QWORDS 8
static_assert(sizeof(struct arm_smmu_ste) == NUM_ENTRY_QWORDS * sizeof(u64));
+static_assert(sizeof(struct arm_smmu_cd) == NUM_ENTRY_QWORDS * sizeof(u64));
static phys_addr_t arm_smmu_msi_cfg[ARM_SMMU_MAX_MSIS][3] = {
[EVTQ_MSI_INDEX] = {
@@ -1236,6 +1237,67 @@ static struct arm_smmu_cd *arm_smmu_get_cd_ptr(struct arm_smmu_master *master,
return &l1_desc->l2ptr[idx];
}
+struct arm_smmu_cd_writer {
+ struct arm_smmu_entry_writer writer;
+ unsigned int ssid;
+};
+
+static void arm_smmu_get_cd_used(const __le64 *ent, __le64 *used_bits)
+{
+ used_bits[0] = cpu_to_le64(CTXDESC_CD_0_V);
+ if (!(ent[0] & cpu_to_le64(CTXDESC_CD_0_V)))
+ return;
+ memset(used_bits, 0xFF, sizeof(struct arm_smmu_cd));
+
+ /* EPD0 means T0SZ/TG0/IR0/OR0/SH0/TTB0 are IGNORED */
+ if (ent[0] & cpu_to_le64(CTXDESC_CD_0_TCR_EPD0)) {
+ used_bits[0] &= ~cpu_to_le64(
+ CTXDESC_CD_0_TCR_T0SZ | CTXDESC_CD_0_TCR_TG0 |
+ CTXDESC_CD_0_TCR_IRGN0 | CTXDESC_CD_0_TCR_ORGN0 |
+ CTXDESC_CD_0_TCR_SH0);
+ used_bits[1] &= ~cpu_to_le64(CTXDESC_CD_1_TTB0_MASK);
+ }
+}
+
+static void arm_smmu_cd_writer_sync_entry(struct arm_smmu_entry_writer *writer)
+{
+ struct arm_smmu_cd_writer *cd_writer =
+ container_of(writer, struct arm_smmu_cd_writer, writer);
+
+ arm_smmu_sync_cd(writer->master, cd_writer->ssid, true);
+}
+
+static const struct arm_smmu_entry_writer_ops arm_smmu_cd_writer_ops = {
+ .sync = arm_smmu_cd_writer_sync_entry,
+ .get_used = arm_smmu_get_cd_used,
+ .v_bit = cpu_to_le64(CTXDESC_CD_0_V),
+};
+
+static void arm_smmu_write_cd_entry(struct arm_smmu_master *master, int ssid,
+ struct arm_smmu_cd *cdptr,
+ const struct arm_smmu_cd *target)
+{
+ struct arm_smmu_cd_writer cd_writer = {
+ .writer = {
+ .ops = &arm_smmu_cd_writer_ops,
+ .master = master,
+ },
+ .ssid = ssid,
+ };
+
+ arm_smmu_write_entry(&cd_writer.writer, cdptr->data, target->data);
+}
+
+static void arm_smmu_clean_cd_entry(struct arm_smmu_cd *target)
+{
+ struct arm_smmu_cd used = {};
+ int i;
+
+ arm_smmu_get_cd_used(target->data, used.data);
+ for (i = 0; i != ARRAY_SIZE(target->data); i++)
+ target->data[i] &= used.data[i];
+}
+
int arm_smmu_write_ctx_desc(struct arm_smmu_master *master, int ssid,
struct arm_smmu_ctx_desc *cd)
{
@@ -1252,17 +1314,20 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_master *master, int ssid,
*/
u64 val;
bool cd_live;
- struct arm_smmu_cd *cdptr;
+ struct arm_smmu_cd target;
+ struct arm_smmu_cd *cdptr = ⌖
+ struct arm_smmu_cd *cd_table_entry;
struct arm_smmu_ctx_desc_cfg *cd_table = &master->cd_table;
struct arm_smmu_device *smmu = master->smmu;
if (WARN_ON(ssid >= (1 << cd_table->s1cdmax)))
return -E2BIG;
- cdptr = arm_smmu_get_cd_ptr(master, ssid);
- if (!cdptr)
+ cd_table_entry = arm_smmu_get_cd_ptr(master, ssid);
+ if (!cd_table_entry)
return -ENOMEM;
+ target = *cd_table_entry;
val = le64_to_cpu(cdptr->data[0]);
cd_live = !!(val & CTXDESC_CD_0_V);
@@ -1284,13 +1349,6 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_master *master, int ssid,
cdptr->data[2] = 0;
cdptr->data[3] = cpu_to_le64(cd->mair);
- /*
- * STE may be live, and the SMMU might read dwords of this CD in any
- * order. Ensure that it observes valid values before reading
- * V=1.
- */
- arm_smmu_sync_cd(master, ssid, true);
-
val = cd->tcr |
#ifdef __BIG_ENDIAN
CTXDESC_CD_0_ENDI |
@@ -1304,18 +1362,14 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_master *master, int ssid,
if (cd_table->stall_enabled)
val |= CTXDESC_CD_0_S;
}
-
+ cdptr->data[0] = cpu_to_le64(val);
/*
- * The SMMU accesses 64-bit values atomically. See IHI0070Ca 3.21.3
- * "Configuration structures and configuration invalidation completion"
- *
- * The size of single-copy atomic reads made by the SMMU is
- * IMPLEMENTATION DEFINED but must be at least 64 bits. Any single
- * field within an aligned 64-bit span of a structure can be altered
- * without first making the structure invalid.
+ * Since the above is updating the CD entry based on the current value
+ * without zeroing unused bits it needs fixing before being passed to
+ * the programming logic.
*/
- WRITE_ONCE(cdptr->data[0], cpu_to_le64(val));
- arm_smmu_sync_cd(master, ssid, true);
+ arm_smmu_clean_cd_entry(&target);
+ arm_smmu_write_cd_entry(master, ssid, cd_table_entry, &target);
return 0;
}