From 58c122cd863f185fd0137a8607df91d6e27574d3 Mon Sep 17 00:00:00 2001
From: Daniel Cederman <cederman@gaisler.com>
Date: Wed, 10 Sep 2014 13:39:53 +0200
Subject: bsp/sparc: Ensure that data cache snooping is enabled

Check that data cache snooping exists and is enabled on all cores.
---
 c/src/lib/libbsp/shared/include/fatal.h       |  2 ++
 c/src/lib/libbsp/sparc/leon3/include/leon.h   | 12 ++++++++++++
 c/src/lib/libbsp/sparc/leon3/startup/bspsmp.c | 15 +++++++++++++--
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/c/src/lib/libbsp/shared/include/fatal.h b/c/src/lib/libbsp/shared/include/fatal.h
index c650a91b8b..640651cb27 100644
--- a/c/src/lib/libbsp/shared/include/fatal.h
+++ b/c/src/lib/libbsp/shared/include/fatal.h
@@ -50,6 +50,8 @@ typedef enum {
   LEON3_FATAL_NO_IRQMP_CONTROLLER = BSP_FATAL_CODE_BLOCK(2),
   LEON3_FATAL_CONSOLE_REGISTER_DEV,
   LEON3_FATAL_CLOCK_INITIALIZATION,
+  LEON3_FATAL_INVALID_CACHE_CONFIG_MAIN_PROCESSOR,
+  LEON3_FATAL_INVALID_CACHE_CONFIG_SECONDARY_PROCESSOR,
 
   /* LPC24XX fatal codes */
   LPC24XX_FATAL_PL111_SET_UP = BSP_FATAL_CODE_BLOCK(3),
diff --git a/c/src/lib/libbsp/sparc/leon3/include/leon.h b/c/src/lib/libbsp/sparc/leon3/include/leon.h
index e2a05f4819..61afbc9567 100644
--- a/c/src/lib/libbsp/sparc/leon3/include/leon.h
+++ b/c/src/lib/libbsp/sparc/leon3/include/leon.h
@@ -119,6 +119,13 @@ extern "C" {
 #define LEON_REG_UART_CTRL_FL     0x00000040 /* Flow control enable */
 #define LEON_REG_UART_CTRL_LB     0x00000080 /* Loop Back enable */
 
+/*
+ *  The following defines the bits in the LEON Cache Control Register.
+ */
+
+#define LEON3_REG_CACHE_CTRL_FI      0x00200000 /* Flush instruction cache */
+#define LEON3_REG_CACHE_CTRL_DS      0x00800000 /* Data cache snooping */
+
 /* LEON3 Interrupt Controller */
 extern volatile struct irqmp_regs *LEON3_IrqCtrl_Regs;
 /* LEON3 GP Timer */
@@ -408,6 +415,11 @@ static inline uint32_t leon3_get_cache_control_register(void)
   return leon3_get_system_register(0x0);
 }
 
+static inline bool leon3_data_cache_snooping_enabled(void)
+{
+  return leon3_get_cache_control_register() & LEON3_REG_CACHE_CTRL_DS;
+}
+
 static inline uint32_t leon3_get_inst_cache_config_register(void)
 {
   return leon3_get_system_register(0x8);
diff --git a/c/src/lib/libbsp/sparc/leon3/startup/bspsmp.c b/c/src/lib/libbsp/sparc/leon3/startup/bspsmp.c
index b90fb2f094..b924479f3d 100644
--- a/c/src/lib/libbsp/sparc/leon3/startup/bspsmp.c
+++ b/c/src/lib/libbsp/sparc/leon3/startup/bspsmp.c
@@ -15,6 +15,8 @@
 
 #include <bsp.h>
 #include <bsp/bootcard.h>
+#include <bsp/fatal.h>
+#include <cache_.h>
 #include <leon.h>
 #include <rtems/bspIo.h>
 #include <rtems/score/smpimpl.h>
@@ -38,7 +40,15 @@ void bsp_start_on_secondary_processor()
 {
   uint32_t cpu_index_self = _CPU_SMP_Get_current_processor();
 
-  leon3_set_cache_control_register(0x80000F);
+  /*
+   * If data cache snooping is not enabled we terminate using
+   * BSP_fatal_exit instead of bsp_fatal. This is done since
+   * the latter function tries to acquire a ticket lock, an
+   * operation which requires data cache snooping to be enabled.
+   */
+  if ( ! leon3_data_cache_snooping_enabled() )
+    BSP_fatal_exit( LEON3_FATAL_INVALID_CACHE_CONFIG_SECONDARY_PROCESSOR );
+
   /* Unmask IPI interrupts at Interrupt controller for this CPU */
   LEON3_IrqCtrl_Regs->mask[cpu_index_self] |= 1U << LEON3_MP_IRQ;
 
@@ -47,7 +57,8 @@ void bsp_start_on_secondary_processor()
 
 uint32_t _CPU_SMP_Initialize( void )
 {
-  leon3_set_cache_control_register(0x80000F);
+  if ( ! leon3_data_cache_snooping_enabled() )
+    bsp_fatal( LEON3_FATAL_INVALID_CACHE_CONFIG_MAIN_PROCESSOR );
 
   if ( rtems_configuration_get_maximum_processors() > 1 ) {
     LEON_Unmask_interrupt(LEON3_MP_IRQ);
-- 
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