ARM: vexpress/TC2: add cpu clock support (4d910d5b) · Commits · 戴 / test

arch/arm/mach-vexpress/spc.c

+102 −0

Original line number	Diff line number	Diff line
		@@ -17,6 +17,9 @@
		* GNU General Public License for more details.
		*/

		#include <linux/clk-provider.h>
		#include <linux/clkdev.h>
		#include <linux/cpu.h>
		#include <linux/delay.h>
		#include <linux/err.h>
		#include <linux/interrupt.h>
		@@ -438,3 +441,102 @@ int __init ve_spc_init(void __iomem *baseaddr, u32 a15_clusid, int irq)

		return 0;
		}

		struct clk_spc {
		struct clk_hw hw;
		int cluster;
		};

		#define to_clk_spc(spc) container_of(spc, struct clk_spc, hw)
		static unsigned long spc_recalc_rate(struct clk_hw *hw,
		unsigned long parent_rate)
		{
		struct clk_spc *spc = to_clk_spc(hw);
		u32 freq;

		if (ve_spc_get_performance(spc->cluster, &freq))
		return -EIO;

		return freq * 1000;
		}

		static long spc_round_rate(struct clk_hw *hw, unsigned long drate,
		unsigned long *parent_rate)
		{
		struct clk_spc *spc = to_clk_spc(hw);

		return ve_spc_round_performance(spc->cluster, drate);
		}

		static int spc_set_rate(struct clk_hw *hw, unsigned long rate,
		unsigned long parent_rate)
		{
		struct clk_spc *spc = to_clk_spc(hw);

		return ve_spc_set_performance(spc->cluster, rate / 1000);
		}

		static struct clk_ops clk_spc_ops = {
		.recalc_rate = spc_recalc_rate,
		.round_rate = spc_round_rate,
		.set_rate = spc_set_rate,
		};

		static struct clk ve_spc_clk_register(struct device cpu_dev)
		{
		struct clk_init_data init;
		struct clk_spc *spc;

		spc = kzalloc(sizeof(*spc), GFP_KERNEL);
		if (!spc) {
		pr_err("could not allocate spc clk\n");
		return ERR_PTR(-ENOMEM);
		}

		spc->hw.init = &init;
		spc->cluster = topology_physical_package_id(cpu_dev->id);

		init.name = dev_name(cpu_dev);
		init.ops = &clk_spc_ops;
		init.flags = CLK_IS_ROOT \| CLK_GET_RATE_NOCACHE;
		init.num_parents = 0;

		return devm_clk_register(cpu_dev, &spc->hw);
		}

		static int __init ve_spc_clk_init(void)
		{
		int cpu;
		struct clk *clk;

		if (!info)
		return 0; /* Continue only if SPC is initialised */

		if (ve_spc_populate_opps(0) \|\| ve_spc_populate_opps(1)) {
		pr_err("failed to build OPP table\n");
		return -ENODEV;
		}

		for_each_possible_cpu(cpu) {
		struct device *cpu_dev = get_cpu_device(cpu);
		if (!cpu_dev) {
		pr_warn("failed to get cpu%d device\n", cpu);
		continue;
		}
		clk = ve_spc_clk_register(cpu_dev);
		if (IS_ERR(clk)) {
		pr_warn("failed to register cpu%d clock\n", cpu);
		continue;
		}
		if (clk_register_clkdev(clk, NULL, dev_name(cpu_dev))) {
		pr_warn("failed to register cpu%d clock lookup\n", cpu);
		continue;
		}

		if (ve_init_opp_table(cpu_dev))
		pr_warn("failed to initialise cpu%d opp table\n", cpu);
		}

		return 0;
		}
		module_init(ve_spc_clk_init);

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