clk: Add clock driver for mb86s7x

 The CRG11 clock controller is managed by remote f/w.
This driver simply maps Linux CLK ops onto mailbox api.

Signed-off-by: Andy Green <andy.green@linaro.org>
Signed-off-by: Vincent Yang <vincent.yang@socionext.com>
Signed-off-by: Tetsuya Nuriya <nuriya.tetsuya@socionext.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

3 files changed, 413 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/clock/fujitsu,mb86s70-crg11.txt b/Documentation/devicetree/bindings/clock/fujitsu,mb86s70-crg11.txt
new file mode 100644
index 000000000000..332396265689
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/fujitsu,mb86s70-crg11.txt
@@ -0,0 +1,26 @@
+Fujitsu CRG11 clock driver bindings
+-----------------------------------
+
+Required properties :
+- compatible : Shall contain "fujitsu,mb86s70-crg11"
+- #clock-cells : Shall be 3 {cntrlr domain port}
+
+The consumer specifies the desired clock pointing to its phandle.
+
+Example:
+
+        clock: crg11 {
+                compatible = "fujitsu,mb86s70-crg11";
+                #clock-cells = <3>;
+        };
+
+        mhu: mhu0@2b1f0000 {
+                #mbox-cells = <1>;
+                compatible = "arm,mhu";
+                reg = <0 0x2B1F0000 0x1000>;
+                interrupts = <0 36 4>, /* LP Non-Sec */
+                             <0 35 4>, /* HP Non-Sec */
+                             <0 37 4>; /* Secure */
+                clocks = <&clock 0 2 1>; /* Cntrlr:0 Domain:2 Port:1 */
+                clock-names = "clk";
+        };
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index d478ceb69c5f..1d35f3bb28e0 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_MACH_LOONGSON1)		+= clk-ls1x.o
 obj-$(CONFIG_COMMON_CLK_MAX_GEN)        += clk-max-gen.o
 obj-$(CONFIG_COMMON_CLK_MAX77686)       += clk-max77686.o
 obj-$(CONFIG_COMMON_CLK_MAX77802)       += clk-max77802.o
+obj-$(CONFIG_ARCH_MB86S7X)              += clk-mb86s7x.o
 obj-$(CONFIG_ARCH_MOXART)               += clk-moxart.o
 obj-$(CONFIG_ARCH_NOMADIK)              += clk-nomadik.o
 obj-$(CONFIG_ARCH_NSPIRE)               += clk-nspire.o
diff --git a/drivers/clk/clk-mb86s7x.c b/drivers/clk/clk-mb86s7x.c
new file mode 100644
index 000000000000..f39c25a22f43
--- /dev/null
+++ b/drivers/clk/clk-mb86s7x.c
@@ -0,0 +1,386 @@
+/*
+ * Copyright (C) 2013-2015 FUJITSU SEMICONDUCTOR LIMITED
+ * Copyright (C) 2015 Linaro Ltd.
+ *
+ * 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, version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/cpu.h>
+#include <linux/clk-provider.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/topology.h>
+#include <linux/mailbox_client.h>
+#include <linux/platform_device.h>
+
+#include <soc/mb86s7x/scb_mhu.h>
+
+#define to_crg_clk(p) container_of(p, struct crg_clk, hw)
+#define to_clc_clk(p) container_of(p, struct cl_clk, hw)
+
+struct mb86s7x_peri_clk {
+        u32 payload_size;
+        u32 cntrlr;
+        u32 domain;
+        u32 port;
+        u32 en;
+        u64 frequency;
+} __packed __aligned(4);
+
+struct hack_rate {
+        unsigned clk_id;
+        unsigned long rate;
+        int gated;
+};
+
+struct crg_clk {
+        struct clk_hw hw;
+        u8 cntrlr, domain, port;
+};
+
+static int crg_gate_control(struct clk_hw *hw, int en)
+{
+        struct crg_clk *crgclk = to_crg_clk(hw);
+        struct mb86s7x_peri_clk cmd;
+        int ret;
+
+        cmd.payload_size = sizeof(cmd);
+        cmd.cntrlr = crgclk->cntrlr;
+        cmd.domain = crgclk->domain;
+        cmd.port = crgclk->port;
+        cmd.en = en;
+
+        /* Port is UngatedCLK */
+        if (cmd.port == 8)
+                return en ? 0 : -EINVAL;
+
+        pr_debug("%s:%d CMD Cntrlr-%u Dom-%u Port-%u En-%u}\n",
+                 __func__, __LINE__, cmd.cntrlr,
+                 cmd.domain, cmd.port, cmd.en);
+
+        ret = mb86s7x_send_packet(CMD_PERI_CLOCK_GATE_SET_REQ,
+                                  &cmd, sizeof(cmd));
+        if (ret < 0) {
+                pr_err("%s:%d failed!\n", __func__, __LINE__);
+                return ret;
+        }
+
+        pr_debug("%s:%d REP Cntrlr-%u Dom-%u Port-%u En-%u}\n",
+                 __func__, __LINE__, cmd.cntrlr,
+                 cmd.domain, cmd.port, cmd.en);
+
+        /* If the request was rejected */
+        if (cmd.en != en)
+                ret = -EINVAL;
+        else
+                ret = 0;
+
+        return ret;
+}
+
+static int crg_port_prepare(struct clk_hw *hw)
+{
+        return crg_gate_control(hw, 1);
+}
+
+static void crg_port_unprepare(struct clk_hw *hw)
+{
+        crg_gate_control(hw, 0);
+}
+
+static int
+crg_rate_control(struct clk_hw *hw, int set, unsigned long *rate)
+{
+        struct crg_clk *crgclk = to_crg_clk(hw);
+        struct mb86s7x_peri_clk cmd;
+        int code, ret;
+
+        cmd.payload_size = sizeof(cmd);
+        cmd.cntrlr = crgclk->cntrlr;
+        cmd.domain = crgclk->domain;
+        cmd.port = crgclk->port;
+        cmd.frequency = *rate;
+
+        if (set) {
+                code = CMD_PERI_CLOCK_RATE_SET_REQ;
+                pr_debug("%s:%d CMD Cntrlr-%u Dom-%u Port-%u Rate-SET %lluHz}\n",
+                         __func__, __LINE__, cmd.cntrlr,
+                         cmd.domain, cmd.port, cmd.frequency);
+        } else {
+                code = CMD_PERI_CLOCK_RATE_GET_REQ;
+                pr_debug("%s:%d CMD Cntrlr-%u Dom-%u Port-%u Rate-GET}\n",
+                         __func__, __LINE__, cmd.cntrlr,
+                         cmd.domain, cmd.port);
+        }
+
+        ret = mb86s7x_send_packet(code, &cmd, sizeof(cmd));
+        if (ret < 0) {
+                pr_err("%s:%d failed!\n", __func__, __LINE__);
+                return ret;
+        }
+
+        if (set)
+                pr_debug("%s:%d REP Cntrlr-%u Dom-%u Port-%u Rate-SET %lluHz}\n",
+                         __func__, __LINE__, cmd.cntrlr,
+                         cmd.domain, cmd.port, cmd.frequency);
+        else
+                pr_debug("%s:%d REP Cntrlr-%u Dom-%u Port-%u Rate-GOT %lluHz}\n",
+                         __func__, __LINE__, cmd.cntrlr,
+                         cmd.domain, cmd.port, cmd.frequency);
+
+        *rate = cmd.frequency;
+        return 0;
+}
+
+static unsigned long
+crg_port_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+        unsigned long rate;
+
+        crg_rate_control(hw, 0, &rate);
+
+        return rate;
+}
+
+static long
+crg_port_round_rate(struct clk_hw *hw,
+                    unsigned long rate, unsigned long *pr)
+{
+        return rate;
+}
+
+static int
+crg_port_set_rate(struct clk_hw *hw,
+                  unsigned long rate, unsigned long parent_rate)
+{
+        return crg_rate_control(hw, 1, &rate);
+}
+
+const struct clk_ops crg_port_ops = {
+        .prepare = crg_port_prepare,
+        .unprepare = crg_port_unprepare,
+        .recalc_rate = crg_port_recalc_rate,
+        .round_rate = crg_port_round_rate,
+        .set_rate = crg_port_set_rate,
+};
+
+struct mb86s70_crg11 {
+        struct mutex lock; /* protects CLK populating and searching */
+};
+
+static struct clk *crg11_get(struct of_phandle_args *clkspec, void *data)
+{
+        struct mb86s70_crg11 *crg11 = data;
+        struct clk_init_data init;
+        u32 cntrlr, domain, port;
+        struct crg_clk *crgclk;
+        struct clk *clk;
+        char clkp[20];
+
+        if (clkspec->args_count != 3)
+                return ERR_PTR(-EINVAL);
+
+        cntrlr = clkspec->args[0];
+        domain = clkspec->args[1];
+        port = clkspec->args[2];
+
+        if (port > 7)
+                snprintf(clkp, 20, "UngatedCLK%d_%X", cntrlr, domain);
+        else
+                snprintf(clkp, 20, "CLK%d_%X_%d", cntrlr, domain, port);
+
+        mutex_lock(&crg11->lock);
+
+        clk = __clk_lookup(clkp);
+        if (clk) {
+                mutex_unlock(&crg11->lock);
+                return clk;
+        }
+
+        crgclk = kzalloc(sizeof(*crgclk), GFP_KERNEL);
+        if (!crgclk) {
+                mutex_unlock(&crg11->lock);
+                return ERR_PTR(-ENOMEM);
+        }
+
+        init.name = clkp;
+        init.num_parents = 0;
+        init.ops = &crg_port_ops;
+        init.flags = CLK_IS_ROOT;
+        crgclk->hw.init = &init;
+        crgclk->cntrlr = cntrlr;
+        crgclk->domain = domain;
+        crgclk->port = port;
+        clk = clk_register(NULL, &crgclk->hw);
+        if (IS_ERR(clk))
+                pr_err("%s:%d Error!\n", __func__, __LINE__);
+        else
+                pr_debug("Registered %s\n", clkp);
+
+        clk_register_clkdev(clk, clkp, NULL);
+        mutex_unlock(&crg11->lock);
+        return clk;
+}
+
+static void __init crg_port_init(struct device_node *node)
+{
+        struct mb86s70_crg11 *crg11;
+
+        crg11 = kzalloc(sizeof(*crg11), GFP_KERNEL);
+        if (!crg11)
+                return;
+
+        mutex_init(&crg11->lock);
+
+        of_clk_add_provider(node, crg11_get, crg11);
+}
+CLK_OF_DECLARE(crg11_gate, "fujitsu,mb86s70-crg11", crg_port_init);
+
+struct cl_clk {
+        struct clk_hw hw;
+        int cluster;
+};
+
+struct mb86s7x_cpu_freq {
+        u32 payload_size;
+        u32 cluster_class;
+        u32 cluster_id;
+        u32 cpu_id;
+        u64 frequency;
+};
+
+static void mhu_cluster_rate(struct clk_hw *hw, unsigned long *rate, int get)
+{
+        struct cl_clk *clc = to_clc_clk(hw);
+        struct mb86s7x_cpu_freq cmd;
+        int code, ret;
+
+        cmd.payload_size = sizeof(cmd);
+        cmd.cluster_class = 0;
+        cmd.cluster_id = clc->cluster;
+        cmd.cpu_id = 0;
+        cmd.frequency = *rate;
+
+        if (get)
+                code = CMD_CPU_CLOCK_RATE_GET_REQ;
+        else
+                code = CMD_CPU_CLOCK_RATE_SET_REQ;
+
+        pr_debug("%s:%d CMD Cl_Class-%u CL_ID-%u CPU_ID-%u Freq-%llu}\n",
+                 __func__, __LINE__, cmd.cluster_class,
+                 cmd.cluster_id, cmd.cpu_id, cmd.frequency);
+
+        ret = mb86s7x_send_packet(code, &cmd, sizeof(cmd));
+        if (ret < 0) {
+                pr_err("%s:%d failed!\n", __func__, __LINE__);
+                return;
+        }
+
+        pr_debug("%s:%d REP Cl_Class-%u CL_ID-%u CPU_ID-%u Freq-%llu}\n",
+                 __func__, __LINE__, cmd.cluster_class,
+                 cmd.cluster_id, cmd.cpu_id, cmd.frequency);
+
+        *rate = cmd.frequency;
+}
+
+static unsigned long
+clc_recalc_rate(struct clk_hw *hw, unsigned long unused)
+{
+        unsigned long rate;
+
+        mhu_cluster_rate(hw, &rate, 1);
+        return rate;
+}
+
+static long
+clc_round_rate(struct clk_hw *hw, unsigned long rate,
+               unsigned long *unused)
+{
+        return rate;
+}
+
+static int
+clc_set_rate(struct clk_hw *hw, unsigned long rate,
+             unsigned long unused)
+{
+        unsigned long res = rate;
+
+        mhu_cluster_rate(hw, &res, 0);
+
+        return (res == rate) ? 0 : -EINVAL;
+}
+
+static struct clk_ops clk_clc_ops = {
+        .recalc_rate = clc_recalc_rate,
+        .round_rate = clc_round_rate,
+        .set_rate = clc_set_rate,
+};
+
+struct clk *mb86s7x_clclk_register(struct device *cpu_dev)
+{
+        struct clk_init_data init;
+        struct cl_clk *clc;
+
+        clc = kzalloc(sizeof(*clc), GFP_KERNEL);
+        if (!clc)
+                return ERR_PTR(-ENOMEM);
+
+        clc->hw.init = &init;
+        clc->cluster = topology_physical_package_id(cpu_dev->id);
+
+        init.name = dev_name(cpu_dev);
+        init.ops = &clk_clc_ops;
+        init.flags = CLK_IS_ROOT | CLK_GET_RATE_NOCACHE;
+        init.num_parents = 0;
+
+        return devm_clk_register(cpu_dev, &clc->hw);
+}
+
+static int mb86s7x_clclk_of_init(void)
+{
+        int cpu, ret = -ENODEV;
+        struct device_node *np;
+        struct clk *clk;
+
+        np = of_find_compatible_node(NULL, NULL, "fujitsu,mb86s70-scb-1.0");
+        if (!np || !of_device_is_available(np))
+                goto exit;
+
+        for_each_possible_cpu(cpu) {
+                struct device *cpu_dev = get_cpu_device(cpu);
+
+                if (!cpu_dev) {
+                        pr_err("failed to get cpu%d device\n", cpu);
+                        continue;
+                }
+
+                clk = mb86s7x_clclk_register(cpu_dev);
+                if (IS_ERR(clk)) {
+                        pr_err("failed to register cpu%d clock\n", cpu);
+                        continue;
+                }
+                if (clk_register_clkdev(clk, NULL, dev_name(cpu_dev))) {
+                        pr_err("failed to register cpu%d clock lookup\n", cpu);
+                        continue;
+                }
+                pr_debug("registered clk for %s\n", dev_name(cpu_dev));
+        }
+        ret = 0;
+
+        platform_device_register_simple("arm-bL-cpufreq-dt", -1, NULL, 0);
+exit:
+        of_node_put(np);
+        return ret;
+}
+module_init(mb86s7x_clclk_of_init);