MIPS: Lemote 2F: Add cs5536 MFGPT timer support

CPUFreq support for Loongson 2F requires an external timer.

Because the frequency of the MIPS Timer is related to the CPU frequency
which itself is variable another timer of constant frequency is required.

Export the mfgpt0 counter disable / enable operations for the coming
suspend support to suspend / resume the timer.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: cpufreq@vger.kernel.org,
Cc: Dave Jones <davej@redhat.com>,
Cc: Dominik Brodowski <linux@dominikbrodowski.net>,
Cc: yanh@lemote.com
Cc: huhb@lemote.com,
Patchwork: http://patchwork.linux-mips.org/patch/658/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/mips/loongson/Kconfig b/arch/mips/loongson/Kconfig
index 17e72fde908c..8b5cc138611a 100644
--- a/arch/mips/loongson/Kconfig
+++ b/arch/mips/loongson/Kconfig
@@ -62,6 +62,17 @@ endchoice
 config CS5536
         bool
 
+config CS5536_MFGPT
+        bool "CS5536 MFGPT Timer"
+        depends on CS5536
+        help
+          This option enables the mfgpt0 timer of AMD CS5536.
+
+          If you want to enable the Loongson2 CPUFreq Driver, Please enable
+          this option at first, otherwise, You will get wrong system time.
+
+          If unsure, say Yes.
+
 config LOONGSON_SUSPEND
         bool
         default y