Initial import

1 files changed, 80 insertions, 0 deletions

diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
new file mode 100644
index 000000000..11964501c
--- /dev/null
+++ b/arch/mips/kernel/mips-cpc.c
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2013 Imagination Technologies
+ * Author: Paul Burton <paul.burton@imgtec.com>
+ *
+ * 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;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/errno.h>
+#include <linux/percpu.h>
+#include <linux/spinlock.h>
+
+#include <asm/mips-cm.h>
+#include <asm/mips-cpc.h>
+
+void __iomem *mips_cpc_base;
+
+static DEFINE_PER_CPU_ALIGNED(spinlock_t, cpc_core_lock);
+
+static DEFINE_PER_CPU_ALIGNED(unsigned long, cpc_core_lock_flags);
+
+phys_addr_t __weak mips_cpc_phys_base(void)
+{
+	u32 cpc_base;
+
+	if (!mips_cm_present())
+		return 0;
+
+	if (!(read_gcr_cpc_status() & CM_GCR_CPC_STATUS_EX_MSK))
+		return 0;
+
+	/* If the CPC is already enabled, leave it so */
+	cpc_base = read_gcr_cpc_base();
+	if (cpc_base & CM_GCR_CPC_BASE_CPCEN_MSK)
+		return cpc_base & CM_GCR_CPC_BASE_CPCBASE_MSK;
+
+	/* Otherwise, give it the default address & enable it */
+	cpc_base = mips_cpc_default_phys_base();
+	write_gcr_cpc_base(cpc_base | CM_GCR_CPC_BASE_CPCEN_MSK);
+	return cpc_base;
+}
+
+int mips_cpc_probe(void)
+{
+	phys_addr_t addr;
+	unsigned cpu;
+
+	for_each_possible_cpu(cpu)
+		spin_lock_init(&per_cpu(cpc_core_lock, cpu));
+
+	addr = mips_cpc_phys_base();
+	if (!addr)
+		return -ENODEV;
+
+	mips_cpc_base = ioremap_nocache(addr, 0x8000);
+	if (!mips_cpc_base)
+		return -ENXIO;
+
+	return 0;
+}
+
+void mips_cpc_lock_other(unsigned int core)
+{
+	unsigned curr_core;
+	preempt_disable();
+	curr_core = current_cpu_data.core;
+	spin_lock_irqsave(&per_cpu(cpc_core_lock, curr_core),
+			  per_cpu(cpc_core_lock_flags, curr_core));
+	write_cpc_cl_other(core << CPC_Cx_OTHER_CORENUM_SHF);
+}
+
+void mips_cpc_unlock_other(void)
+{
+	unsigned curr_core = current_cpu_data.core;
+	spin_unlock_irqrestore(&per_cpu(cpc_core_lock, curr_core),
+			       per_cpu(cpc_core_lock_flags, curr_core));
+	preempt_enable();
+}