[PATCH 1/3] microblaze: Add xmb_manager_register function

From: Appana Durga Kedareswara rao
Date: Mon Jun 27 2022 - 02:41:03 EST


Triple Modular Redundancy (TMR) Microblaze solution provides soft error
injection, detection, correction and recovery for Microblaze cores in the
system. The Xilinx/AMD Triple Modular Redundancy (TMR) solution in Vivado
provides all the necessary building blocks to implement a redundant
triplicated MicroBlaze subsystem. This processing subsystem is
fault-tolerant and continues to operate nominally after encountering an
error. Together with the capability to detect and recover from errors,
the implementation ensures the reliability of the entire subsystem.

When the break vector gets asserted because of error injection,
the break signal must be blocked before exiting from the break handler,
This commit adds support for xmb_manager_register api which updates the
TMR manager address and control register and error count and reset callback
function arguments, which will be used by the break handler to block the
break and call the error count callback function and reset callback
function.

Signed-off-by: Appana Durga Kedareswara rao <appana.durga.rao@xxxxxxxxxx>
---
arch/microblaze/Kconfig | 10 +++++
.../include/asm/xilinx_mb_manager.h | 21 +++++++++
arch/microblaze/kernel/entry.S | 44 +++++++++++++++++++
3 files changed, 75 insertions(+)
create mode 100644 arch/microblaze/include/asm/xilinx_mb_manager.h

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index 8cf429ad1c84..7bcab7357f42 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -206,6 +206,16 @@ config TASK_SIZE
hex "Size of user task space" if TASK_SIZE_BOOL
default "0x80000000"

+config MB_MANAGER
+ bool "Support for Microblaze Manager"
+ depends on ADVANCED_OPTIONS
+ help
+ This option enables API for configuring the MicroBlaze manager
+ control register, which is consumed by the break handler to
+ block the break.
+
+ Say N here unless you know what you are doing.
+
endmenu

menu "Bus Options"
diff --git a/arch/microblaze/include/asm/xilinx_mb_manager.h b/arch/microblaze/include/asm/xilinx_mb_manager.h
new file mode 100644
index 000000000000..392c3aa278dc
--- /dev/null
+++ b/arch/microblaze/include/asm/xilinx_mb_manager.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 Xilinx, Inc.
+ */
+#ifndef _XILINX_MB_MANAGER_H
+#define _XILINX_MB_MANAGER_H
+
+#include <linux/of_address.h>
+
+/*
+ * When the break vector gets asserted because of error injection, the break
+ * signal must be blocked before exiting from the break handler, Below api
+ * updates the manager address and control register and error counter callback
+ * arguments, which will be used by the break handler to block the break and
+ * call the callback function.
+ */
+void xmb_manager_register(uintptr_t phys_baseaddr, u32 cr_val,
+ void (*callback)(void *data),
+ void *priv, void (*reset_callback)(void *data));
+
+#endif /* _XILINX_MB_MANAGER_H */
diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
index b179f8f6d287..b8e1dfe02d58 100644
--- a/arch/microblaze/kernel/entry.S
+++ b/arch/microblaze/kernel/entry.S
@@ -957,6 +957,50 @@ ENTRY(_switch_to)
rtsd r15, 8
nop

+#ifdef CONFIG_MB_MANAGER
+.section .data
+.global xmb_manager_dev
+.global xmb_manager_baseaddr
+.global xmb_manager_crval
+.global xmb_manager_callback
+.global xmb_manager_reset_callback
+.align 4
+xmb_manager_dev:
+ .long 0
+xmb_manager_baseaddr:
+ .long 0
+xmb_manager_crval:
+ .long 0
+xmb_manager_callback:
+ .long 0
+xmb_manager_reset_callback:
+ .long 0
+
+/*
+ * When the break vector gets asserted because of error injection,
+ * the break signal must be blocked before exiting from the
+ * break handler, Below api updates the manager address and
+ * control register and error count callback arguments,
+ * which will be used by the break handler to block the
+ * break and call the callback function.
+ */
+.global xmb_manager_register
+.section .text
+.align 2
+.ent xmb_manager_register
+.type xmb_manager_register, @function
+xmb_manager_register:
+ swi r5, r0, xmb_manager_baseaddr
+ swi r6, r0, xmb_manager_crval
+ swi r7, r0, xmb_manager_callback
+ swi r8, r0, xmb_manager_dev
+ swi r9, r0, xmb_manager_reset_callback
+
+ rtsd r15, 8;
+ nop;
+.end xmb_manager_register
+#endif
+
ENTRY(_reset)
VM_OFF
brai 0; /* Jump to reset vector */
--
2.25.1