[MIPS] Add support for BCM47XX CPUs.

Note that the BCM4710 does not support the wait instruction, this
is not a mistake in the code.
    
It originally comes from the OpenWrt patches.
    
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Felix Fietkau <nbd@openwrt.org>
Cc: Florian Schirmer <jolt@tuxbox.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/arch/mips/bcm47xx/time.c b/arch/mips/bcm47xx/time.c
new file mode 100644
index 00000000000..b27d07f2905
--- /dev/null
+++ b/arch/mips/bcm47xx/time.c
@@ -0,0 +1,56 @@
+/*
+ *  Copyright (C) 2004 Florian Schirmer <jolt@tuxbox.org>
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
+ *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
+ *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
+ *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
+ *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  You should have received a copy of the  GNU General Public License along
+ *  with this program; if not, write  to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <linux/init.h>
+#include <linux/ssb/ssb.h>
+#include <asm/time.h>
+#include <bcm47xx.h>
+
+void __init
+bcm47xx_time_init(void)
+{
+	unsigned long hz;
+
+	/*
+	 * Use deterministic values for initial counter interrupt
+	 * so that calibrate delay avoids encountering a counter wrap.
+	 */
+	write_c0_count(0);
+	write_c0_compare(0xffff);
+
+	hz = ssb_cpu_clock(&ssb_bcm47xx.mipscore) / 2;
+	if (!hz)
+		hz = 100000000;
+
+	/* Set MIPS counter frequency for fixed_rate_gettimeoffset() */
+	mips_hpt_frequency = hz;
+}
+
+void __init
+plat_timer_setup(struct irqaction *irq)
+{
+	/* Enable the timer interrupt */
+	setup_irq(7, irq);
+}