[RESEND,2/2] clk: mmp: add support for DT-defined clocks

Commit Message

Mike Turquette Aug. 5, 2013, 10 p.m. UTC

Add support to the existing mmp clock drivers for clocks to be defined
in the device tree. This will be used on OLPC MMP2/MMP3-based laptops.

If clock info cannot be found in the device tree, we fall back to the
static clock initialization already present.

Signed-off-by: Daniel Drake <[e-mail]>
---
 .../devicetree/bindings/clock/mmp-apbc.txt         | 30 ++++++++++
 .../devicetree/bindings/clock/mmp-apmu.txt         | 30 ++++++++++
 drivers/clk/mmp/clk-apbc.c                         | 66 +++++++++++++++++++++-
 drivers/clk/mmp/clk-apmu.c                         | 37 +++++++++++-
 drivers/clk/mmp/clk-mmp2.c                         | 19 ++++++-
 5 files changed, 179 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/clock/mmp-apbc.txt
 create mode 100644 Documentation/devicetree/bindings/clock/mmp-apmu.txt

Resending after a month without review.

Patch

diff --git a/Documentation/devicetree/bindings/clock/mmp-apbc.txt b/Documentation/devicetree/bindings/clock/mmp-apbc.txt
new file mode 100644
index 0000000..88e1253
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/mmp-apbc.txt
@@ -0,0 +1,30 @@ 
+* Clock bindings for Marvell MMP Advanced Peripheral Bus clock
+
+Parent apb-clock node
+=====================
+Required properties:
+- reg: Address and length of the APB clock unit registers
+
+
+Child peripheral clock nodes
+============================
+Required properties:
+- compatible : shall be "marvell,mmp-apb-clock"
+- #clock-cells : from common clock binding; shall be set to 1
+- clocks : parent clock, from common clock binding
+- clock-output-names : Array of clock names, from common clock binding
+- reg : Array of control register offsets into APB clock unit register space
+
+
+Example:
+apbc: apb-clock {
+       reg = <0xd4015000 0x1000>;
+
+       twsi-clocks {
+               compatible = "marvell,mmp-apb-clock";
+               #clock-cells = <1>;
+               clocks = <&vctvxo-clock>;
+               clock-output-names = "TWSI0", "TWSI1";
+               reg = <0x04 0x08>;
+       };
+};
diff --git a/Documentation/devicetree/bindings/clock/mmp-apmu.txt b/Documentation/devicetree/bindings/clock/mmp-apmu.txt
new file mode 100644
index 0000000..18bb0f9
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/mmp-apmu.txt
@@ -0,0 +1,30 @@ 
+* Clock bindings for Marvell MMP Application Subsystem Power Management Unit
+
+Parent apmu-clock node
+=====================
+Required properties:
+- reg: Address and length of the CPU Subsystem PMU registers
+
+
+Child peripheral clock nodes
+============================
+Required properties:
+- compatible : shall be "marvell,mmp-apmu-clock"
+- #clock-cells : from common clock binding; shall be set to 0
+- clocks : parent clock, from common clock binding
+- reg : Control register offsets into parent register space
+- enable-mask : The bits to be set in the register to enable the clock, or
+                cleared to disable.
+
+Example:
+apmu-clock {
+       reg = <0xd4282800 0x1000>;
+
+       usb-clock {
+               compatible = "marvell,mmp-apmu-clock";
+               #clock-cells = <0>;
+               clocks = <&usb_pll>;
+               reg = <0x5c>;
+               enable-mask = <0x09>;
+       };
+};
diff --git a/drivers/clk/mmp/clk-apbc.c b/drivers/clk/mmp/clk-apbc.c
index 89a146a..d53bc79 100644
--- a/drivers/clk/mmp/clk-apbc.c
+++ b/drivers/clk/mmp/clk-apbc.c
@@ -15,6 +15,8 @@ 
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
 
 #include "clk.h"
 
@@ -129,8 +131,70 @@  struct clk *mmp_clk_register_apbc(const char *name, const char *parent_name,
        apbc->hw.init = &init;
 
        clk = clk_register(NULL, &apbc->hw);
-       if (IS_ERR(clk))
+       if (WARN_ON(IS_ERR(clk)))
                kfree(apbc);
 
        return clk;
 }
+
+static void __init mmp_apbc_dt_init(struct device_node *node)
+{
+       struct device_node *parent = of_get_parent(node);
+       const __be32 *regs;
+       struct clk *clk;
+       int rc;
+       int len;
+       int num_clocks;
+       int clock_num;
+       void __iomem *baseaddr;
+       const char *clock_name;
+       const char *parent_name;
+       struct clk **clks;
+       struct clk_onecell_data *clk_data;
+
+       regs = of_get_property(node, "reg", &len);
+       if (WARN_ON(!regs || (len % sizeof(__be32) != 0)))
+               return;
+       num_clocks = len / sizeof(__be32);
+
+       baseaddr = of_iomap(parent, 0);
+       of_node_put(parent);
+       if (WARN_ON(!baseaddr))
+               return;
+
+       clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
+       if (WARN_ON(!clk_data))
+               goto err_clk_data;
+
+       clks = kzalloc(num_clocks * sizeof(*clks), GFP_KERNEL);
+       if (WARN_ON(!clks))
+               goto err_clks;
+
+       clock_name = of_get_property(node, "clock-output-names", NULL);
+       parent_name = of_clk_get_parent_name(node, 0);
+
+       for (clock_num = 0; clock_num < num_clocks; clock_num++) {
+               void __iomem *clock_addr;
+               clock_addr = baseaddr + be32_to_cpup(regs + clock_num);
+
+               clk = mmp_clk_register_apbc(clock_name, parent_name,
+                                           clock_addr, 10, 0);

Looks like mmp_clk_register_apbc is missing an argument for the
spinlock. I'm getting the following:

drivers/clk/mmp/clk-apbc.c: In function ‘mmp_apbc_dt_init’:
drivers/clk/mmp/clk-apbc.c|197 col 10| error: too few arguments to
function ‘mmp_clk_register_apbc’

Regards,
Mike

+               if (IS_ERR(clk))
+                       return;
+               clock_name += strlen(clock_name) + 1;
+               clks[clock_num] = clk;
+       }
+
+       clk_data->clk_num = num_clocks;
+       clk_data->clks = clks;
+       rc = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
+       WARN_ON(rc);
+       return;
+
+err_clks:
+       kfree(clk_data);
+err_clk_data:
+       iounmap(baseaddr);
+
+}
+CLK_OF_DECLARE(mmp2_apbc, "marvell,mmp-apb-clock", mmp_apbc_dt_init);
diff --git a/drivers/clk/mmp/clk-apmu.c b/drivers/clk/mmp/clk-apmu.c
index 4f4d8c5..dfcecc9 100644
--- a/drivers/clk/mmp/clk-apmu.c
+++ b/drivers/clk/mmp/clk-apmu.c
@@ -15,6 +15,8 @@ 
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
 
 #include "clk.h"
 
@@ -22,7 +24,6 @@ 
 struct clk_apmu {
        struct clk_hw   hw;
        void __iomem    *base;
-       u32             rst_mask;
        u32             enable_mask;
 };
 
@@ -85,3 +86,37 @@  struct clk *mmp_clk_register_apmu(const char *name, const char *parent_name,
 
        return clk;
 }
+
+static void __init mmp_apmu_dt_init(struct device_node *node)
+{
+       struct device_node *parent = of_get_parent(node);
+       const char *clk_name = node->name;
+       void __iomem *baseaddr;
+       struct clk *clk;
+       u32 reg;
+       u32 enable_mask;
+       int rc;
+
+       rc = of_property_read_u32(node, "reg", &reg);
+       if (WARN_ON(rc))
+               return;
+
+       rc = of_property_read_u32(node, "enable-mask", &enable_mask);
+       if (WARN_ON(rc))
+               return;
+
+       baseaddr = of_iomap(parent, 0);
+       of_node_put(parent);
+       if (WARN_ON(!baseaddr))
+               return;
+
+       of_property_read_string(node, "clock-output-names", &clk_name);
+       clk = mmp_clk_register_apmu(clk_name, of_clk_get_parent_name(node, 0),
+                                   baseaddr + reg, enable_mask);
+       if (WARN_ON(IS_ERR(clk)))
+               return;
+
+       rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+       WARN_ON(rc);
+}
+CLK_OF_DECLARE(mmp2_apmu, "marvell,mmp-apmu-clock", mmp_apmu_dt_init);
diff --git a/drivers/clk/mmp/clk-mmp2.c b/drivers/clk/mmp/clk-mmp2.c
index cb1b0b6..774193b 100644
--- a/drivers/clk/mmp/clk-mmp2.c
+++ b/drivers/clk/mmp/clk-mmp2.c
@@ -15,6 +15,7 @@ 
 #include <linux/io.h>
 #include <linux/delay.h>
 #include <linux/err.h>
+#include <linux/of.h>
 
 #include <mach/addr-map.h>
 
@@ -73,7 +74,7 @@  static const char *sdh_parent[] = {"pll1_4", "pll2", "usb_pll", "pll1"};
 static const char *disp_parent[] = {"pll1", "pll1_16", "pll2", "vctcxo"};
 static const char *ccic_parent[] = {"pll1_2", "pll1_16", "vctcxo"};
 
-void __init mmp2_clk_init(void)
+static void __init mmp2_clk_init_static(void)
 {
        struct clk *clk;
        struct clk *vctcxo;
@@ -445,3 +446,19 @@  void __init mmp2_clk_init(void)
                                apmu_base + APMU_CCIC1, 0x300);
        clk_register_clkdev(clk, "sphyclk", "mmp-ccic.1");
 }
+
+void __init mmp2_clk_init(void)
+{
+       struct device_node *node;
+
+       /* The presence of the ABP clock node in the device tree indicates
+        * that we should use the DT for clock setup. */
+       node = of_find_compatible_node(NULL, NULL, "marvell,mmp-apb-clock");
+       if (node) {
+               of_node_put(node);
+               of_clk_init(NULL);
+       } else {
+               /* Fallback to static setup */
+               mmp2_clk_init_static();
+       }
+}