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-rw-r--r--Documentation/sh/clk.txt32
-rw-r--r--Documentation/sysrq.txt4
2 files changed, 34 insertions, 2 deletions
diff --git a/Documentation/sh/clk.txt b/Documentation/sh/clk.txt
new file mode 100644
index 000000000000..9aef710e9a4b
--- /dev/null
+++ b/Documentation/sh/clk.txt
@@ -0,0 +1,32 @@
+Clock framework on SuperH architecture
+
+The framework on SH extends existing API by the function clk_set_rate_ex,
+which prototype is as follows:
+
+ clk_set_rate_ex (struct clk *clk, unsigned long rate, int algo_id)
+
+The algo_id parameter is used to specify algorithm used to recalculate clocks,
+adjanced to clock, specified as first argument. It is assumed that algo_id==0
+means no changes to adjanced clock
+
+Internally, the clk_set_rate_ex forwards request to clk->ops->set_rate method,
+if it is present in ops structure. The method should set the clock rate and adjust
+all needed clocks according to the passed algo_id.
+Exact values for algo_id are machine-dependend. For the sh7722, the following
+values are defined:
+
+ NO_CHANGE = 0,
+ IUS_N1_N1, /* I:U = N:1, U:Sh = N:1 */
+ IUS_322, /* I:U:Sh = 3:2:2 */
+ IUS_522, /* I:U:Sh = 5:2:2 */
+ IUS_N11, /* I:U:Sh = N:1:1 */
+ SB_N1, /* Sh:B = N:1 */
+ SB3_N1, /* Sh:B3 = N:1 */
+ SB3_32, /* Sh:B3 = 3:2 */
+ SB3_43, /* Sh:B3 = 4:3 */
+ SB3_54, /* Sh:B3 = 5:4 */
+ BP_N1, /* B:P = N:1 */
+ IP_N1 /* I:P = N:1 */
+
+Each of these constants means relation between clocks that can be set via the FRQCR
+register
diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt
index d43aa9d3c105..ba328f255417 100644
--- a/Documentation/sysrq.txt
+++ b/Documentation/sysrq.txt
@@ -1,6 +1,6 @@
Linux Magic System Request Key Hacks
Documentation for sysrq.c
-Last update: 2007-JAN-06
+Last update: 2007-MAR-14
* What is the magic SysRq key?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -75,7 +75,7 @@ On all - write a character to /proc/sysrq-trigger. e.g.:
'f' - Will call oom_kill to kill a memory hog process.
-'g' - Used by kgdb on ppc platforms.
+'g' - Used by kgdb on ppc and sh platforms.
'h' - Will display help (actually any other key than those listed
above will display help. but 'h' is easy to remember :-)