arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted

__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2.
PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in
HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host
traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The
kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU
driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a
write from EL0 reaches the trap and takes the host down without a panic
message.

Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already
does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9
bits.

Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9")
Cc: stable@vger.kernel.org
Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 48 insertions, 0 deletions

diff --git a/include/soc/qcom/cmd-db.h b/include/soc/qcom/cmd-db.h
new file mode 100644
index 000000000..47a6cab75
--- /dev/null
+++ b/include/soc/qcom/cmd-db.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef __QCOM_COMMAND_DB_H__
+#define __QCOM_COMMAND_DB_H__
+
+#include <linux/err.h>
+
+enum cmd_db_hw_type {
+	CMD_DB_HW_INVALID = 0,
+	CMD_DB_HW_MIN     = 3,
+	CMD_DB_HW_ARC     = CMD_DB_HW_MIN,
+	CMD_DB_HW_VRM     = 4,
+	CMD_DB_HW_BCM     = 5,
+	CMD_DB_HW_MAX     = CMD_DB_HW_BCM,
+	CMD_DB_HW_ALL     = 0xff,
+};
+
+#if IS_ENABLED(CONFIG_QCOM_COMMAND_DB)
+u32 cmd_db_read_addr(const char *resource_id);
+
+const void *cmd_db_read_aux_data(const char *resource_id, size_t *len);
+
+bool cmd_db_match_resource_addr(u32 addr1, u32 addr2);
+
+enum cmd_db_hw_type cmd_db_read_slave_id(const char *resource_id);
+
+int cmd_db_ready(void);
+#else
+static inline u32 cmd_db_read_addr(const char *resource_id)
+{ return 0; }
+
+static inline const void *cmd_db_read_aux_data(const char *resource_id, size_t *len)
+{ return ERR_PTR(-ENODEV); }
+
+static inline bool cmd_db_match_resource_addr(u32 addr1, u32 addr2)
+{ return false; }
+
+static inline enum cmd_db_hw_type cmd_db_read_slave_id(const char *resource_id)
+{ return -ENODEV; }
+
+static inline int cmd_db_ready(void)
+{ return -ENODEV; }
+#endif /* CONFIG_QCOM_COMMAND_DB */
+#endif /* __QCOM_COMMAND_DB_H__ */