microblaze: Add support for CCF

Add support for CCF for Microblaze.

Old binding:
system_timer: system-timer@41c00000 {
	clock-frequency = <75000000>;
	...
}

New binding:
system_timer: system-timer@41c00000 {
	clocks = <&clk_bus>;
	...
}

Both should be supported for a while

Microblaze clock binding:
clocks {
	#address-cells = <1>;
	#size-cells = <0>;
	clk_bus: bus {
		#clock-cells = <0>;
		clock-frequency = <75000000>;
		clock-output-names = "bus";
		compatible = "fixed-clock";
		reg = <1>;
	} ;
	clk_cpu: cpu {
		#clock-cells = <0>;
		clock-frequency = <75000000>;
		clock-output-names = "cpu";
		compatible = "fixed-clock";
		reg = <0>;
	} ;
} ;

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

7 files changed, 40 insertions, 11 deletions

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index e23cccde9c27..a715eeaf9959 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -26,6 +26,7 @@ config MICROBLAZE
         select GENERIC_CPU_DEVICES
         select GENERIC_ATOMIC64
         select GENERIC_CLOCKEVENTS
+        select COMMON_CLK
         select GENERIC_IDLE_POLL_SETUP
         select MODULES_USE_ELF_RELA
         select CLONE_BACKWARDS3
diff --git a/arch/microblaze/include/asm/cpuinfo.h b/arch/microblaze/include/asm/cpuinfo.h
index 7161fb575861..3337417fcdca 100644
--- a/arch/microblaze/include/asm/cpuinfo.h
+++ b/arch/microblaze/include/asm/cpuinfo.h
@@ -91,6 +91,7 @@ extern struct cpuinfo cpuinfo;
 
 /* fwd declarations of the various CPUinfo populators */
 void setup_cpuinfo(void);
+void setup_cpuinfo_clk(void);
 
 void set_cpuinfo_static(struct cpuinfo *ci, struct device_node *cpu);
 void set_cpuinfo_pvr_full(struct cpuinfo *ci, struct device_node *cpu);
diff --git a/arch/microblaze/kernel/cpu/cpuinfo-pvr-full.c b/arch/microblaze/kernel/cpu/cpuinfo-pvr-full.c
index ee4689415410..93c26cf50de5 100644
--- a/arch/microblaze/kernel/cpu/cpuinfo-pvr-full.c
+++ b/arch/microblaze/kernel/cpu/cpuinfo-pvr-full.c
@@ -112,7 +112,4 @@ void set_cpuinfo_pvr_full(struct cpuinfo *ci, struct device_node *cpu)
         CI(num_wr_brk, NUMBER_OF_WR_ADDR_BRK);
 
         CI(fpga_family_code, TARGET_FAMILY);
-
-        /* take timebase-frequency from DTS */
-        ci->cpu_clock_freq = fcpu(cpu, "timebase-frequency");
 }
diff --git a/arch/microblaze/kernel/cpu/cpuinfo-static.c b/arch/microblaze/kernel/cpu/cpuinfo-static.c
index 592bb2e838c4..4854285b26e7 100644
--- a/arch/microblaze/kernel/cpu/cpuinfo-static.c
+++ b/arch/microblaze/kernel/cpu/cpuinfo-static.c
@@ -113,8 +113,6 @@ void __init set_cpuinfo_static(struct cpuinfo *ci, struct device_node *cpu)
         ci->num_rd_brk = fcpu(cpu, "xlnx,number-of-rd-addr-brk");
         ci->num_wr_brk = fcpu(cpu, "xlnx,number-of-wr-addr-brk");
 
-        ci->cpu_clock_freq = fcpu(cpu, "timebase-frequency");
-
         ci->pvr_user1 = fcpu(cpu, "xlnx,pvr-user1");
         ci->pvr_user2 = fcpu(cpu, "xlnx,pvr-user2");
 
diff --git a/arch/microblaze/kernel/cpu/cpuinfo.c b/arch/microblaze/kernel/cpu/cpuinfo.c
index c9203b1007aa..ce1cfed731ea 100644
--- a/arch/microblaze/kernel/cpu/cpuinfo.c
+++ b/arch/microblaze/kernel/cpu/cpuinfo.c
@@ -8,6 +8,7 @@
  * for more details.
  */
 
+#include <linux/clk.h>
 #include <linux/init.h>
 #include <asm/cpuinfo.h>
 #include <asm/pvr.h>
@@ -68,11 +69,10 @@ const struct family_string_key family_string_lookup[] = {
 };
 
 struct cpuinfo cpuinfo;
+static struct device_node *cpu;
 
 void __init setup_cpuinfo(void)
 {
-        struct device_node *cpu = NULL;
-
         cpu = (struct device_node *) of_find_node_by_type(NULL, "cpu");
         if (!cpu)
                 pr_err("You don't have cpu!!!\n");
@@ -102,3 +102,22 @@ void __init setup_cpuinfo(void)
                 pr_warn("%s: Stream instructions enabled"
                         " - USERSPACE CAN LOCK THIS KERNEL!\n", __func__);
 }
+
+void __init setup_cpuinfo_clk(void)
+{
+        struct clk *clk;
+
+        clk = of_clk_get(cpu, 0);
+        if (IS_ERR(clk)) {
+                pr_err("ERROR: CPU CCF input clock not found\n");
+                /* take timebase-frequency from DTS */
+                cpuinfo.cpu_clock_freq = fcpu(cpu, "timebase-frequency");
+        } else {
+                cpuinfo.cpu_clock_freq = clk_get_rate(clk);
+        }
+
+        if (!cpuinfo.cpu_clock_freq) {
+                pr_err("ERROR: CPU clock frequency not setup\n");
+                BUG();
+        }
+}
diff --git a/arch/microblaze/kernel/setup.c b/arch/microblaze/kernel/setup.c
index 603e22fec6d5..9d972d2bd924 100644
--- a/arch/microblaze/kernel/setup.c
+++ b/arch/microblaze/kernel/setup.c
@@ -9,6 +9,7 @@
  */
 
 #include <linux/init.h>
+#include <linux/clk-provider.h>
 #include <linux/clocksource.h>
 #include <linux/string.h>
 #include <linux/seq_file.h>
@@ -195,6 +196,8 @@ void __init machine_early_init(const char *cmdline, unsigned int ram,
 
 void __init time_init(void)
 {
+        of_clk_init(NULL);
+        setup_cpuinfo_clk();
         clocksource_of_init();
 }
 
diff --git a/arch/microblaze/kernel/timer.c b/arch/microblaze/kernel/timer.c
index 3e39b1082fdf..55b19400951f 100644
--- a/arch/microblaze/kernel/timer.c
+++ b/arch/microblaze/kernel/timer.c
@@ -230,9 +230,9 @@ static int timer_initialized;
 
 static void __init xilinx_timer_init(struct device_node *timer)
 {
+        struct clk *clk;
         u32 irq;
         u32 timer_num = 1;
-        int ret;
 
         timer_baseaddr = of_iomap(timer, 0);
         if (!timer_baseaddr) {
@@ -250,10 +250,20 @@ static void __init xilinx_timer_init(struct device_node *timer)
 
         pr_info("%s: irq=%d\n", timer->full_name, irq);
 
-        /* If there is clock-frequency property than use it */
-        ret = of_property_read_u32(timer, "clock-frequency", &timer_clock_freq);
-        if (ret < 0)
+        clk = of_clk_get(timer, 0);
+        if (IS_ERR(clk)) {
+                pr_err("ERROR: timer CCF input clock not found\n");
+                /* If there is clock-frequency property than use it */
+                of_property_read_u32(timer, "clock-frequency",
+                                    &timer_clock_freq);
+        } else {
+                timer_clock_freq = clk_get_rate(clk);
+        }
+
+        if (!timer_clock_freq) {
+                pr_err("ERROR: Using CPU clock frequency\n");
                 timer_clock_freq = cpuinfo.cpu_clock_freq;
+        }
 
         freq_div_hz = timer_clock_freq / HZ;