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authorAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
committerAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
commitb4b6116a13633898cf868f2f103c96a90c4c20f8 (patch)
tree93d1b7e2cfcdf473d8d4ff3ad141fa864f8491f6 /arch/blackfin/kernel/reboot.c
parentedd4be777c953e5faafc80d091d3084b4343f5d3 (diff)
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fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'arch/blackfin/kernel/reboot.c')
-rw-r--r--arch/blackfin/kernel/reboot.c113
1 files changed, 113 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/reboot.c b/arch/blackfin/kernel/reboot.c
new file mode 100644
index 00000000000..c4c0081b199
--- /dev/null
+++ b/arch/blackfin/kernel/reboot.c
@@ -0,0 +1,113 @@
+/*
+ * arch/blackfin/kernel/reboot.c - handle shutdown/reboot
+ *
+ * Copyright 2004-2007 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/interrupt.h>
+#include <asm/bfin-global.h>
+#include <asm/reboot.h>
+#include <asm/system.h>
+#include <asm/bfrom.h>
+
+/* A system soft reset makes external memory unusable so force
+ * this function into L1. We use the compiler ssync here rather
+ * than SSYNC() because it's safe (no interrupts and such) and
+ * we save some L1. We do not need to force sanity in the SYSCR
+ * register as the BMODE selection bit is cleared by the soft
+ * reset while the Core B bit (on dual core parts) is cleared by
+ * the core reset.
+ */
+__attribute__ ((__l1_text__, __noreturn__))
+static void bfin_reset(void)
+{
+ if (!ANOMALY_05000353 && !ANOMALY_05000386)
+ bfrom_SoftReset((void *)(L1_SCRATCH_START + L1_SCRATCH_LENGTH - 20));
+
+ /* Wait for completion of "system" events such as cache line
+ * line fills so that we avoid infinite stalls later on as
+ * much as possible. This code is in L1, so it won't trigger
+ * any such event after this point in time.
+ */
+ __builtin_bfin_ssync();
+
+ /* Initiate System software reset. */
+ bfin_write_SWRST(0x7);
+
+ /* Due to the way reset is handled in the hardware, we need
+ * to delay for 10 SCLKS. The only reliable way to do this is
+ * to calculate the CCLK/SCLK ratio and multiply 10. For now,
+ * we'll assume worse case which is a 1:15 ratio.
+ */
+ asm(
+ "LSETUP (1f, 1f) LC0 = %0\n"
+ "1: nop;"
+ :
+ : "a" (15 * 10)
+ : "LC0", "LB0", "LT0"
+ );
+
+ /* Clear System software reset */
+ bfin_write_SWRST(0);
+
+ /* The BF526 ROM will crash during reset */
+#if defined(__ADSPBF522__) || defined(__ADSPBF524__) || defined(__ADSPBF526__)
+ /* Seems to be fixed with newer parts though ... */
+ if (__SILICON_REVISION__ < 1 && bfin_revid() < 1)
+ bfin_read_SWRST();
+#endif
+
+ /* Wait for the SWRST write to complete. Cannot rely on SSYNC
+ * though as the System state is all reset now.
+ */
+ asm(
+ "LSETUP (1f, 1f) LC1 = %0\n"
+ "1: nop;"
+ :
+ : "a" (15 * 1)
+ : "LC1", "LB1", "LT1"
+ );
+
+ while (1)
+ /* Issue core reset */
+ asm("raise 1");
+}
+
+__attribute__((weak))
+void native_machine_restart(char *cmd)
+{
+}
+
+void machine_restart(char *cmd)
+{
+ native_machine_restart(cmd);
+ local_irq_disable();
+ if (smp_processor_id())
+ smp_call_function((void *)bfin_reset, 0, 1);
+ else
+ bfin_reset();
+}
+
+__attribute__((weak))
+void native_machine_halt(void)
+{
+ idle_with_irq_disabled();
+}
+
+void machine_halt(void)
+{
+ native_machine_halt();
+}
+
+__attribute__((weak))
+void native_machine_power_off(void)
+{
+ idle_with_irq_disabled();
+}
+
+void machine_power_off(void)
+{
+ native_machine_power_off();
+}