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+Content-Type: text/plain; charset="utf-8"
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+Subject: [v3,01/13] ARM: Add Krait L2 register accessor functions
+From: Stephen Boyd <sboyd@codeaurora.org>
+X-Patchwork-Id: 6063051
+Message-Id: <1426920332-9340-2-git-send-email-sboyd@codeaurora.org>
+To: Mike Turquette <mturquette@linaro.org>, Stephen Boyd <sboyd@codeaurora.org>
+Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
+ linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
+ Viresh Kumar <viresh.kumar@linaro.org>,
+ Mark Rutland <mark.rutland@arm.com>, Russell King <linux@arm.linux.org.uk>,
+ Courtney Cavin <courtney.cavin@sonymobile.com>
+Date: Fri, 20 Mar 2015 23:45:20 -0700
+
+Krait CPUs have a handful of L2 cache controller registers that
+live behind a cp15 based indirection register. First you program
+the indirection register (l2cpselr) to point the L2 'window'
+register (l2cpdr) at what you want to read/write. Then you
+read/write the 'window' register to do what you want. The
+l2cpselr register is not banked per-cpu so we must lock around
+accesses to it to prevent other CPUs from re-pointing l2cpdr
+underneath us.
+
+Cc: Mark Rutland <mark.rutland@arm.com>
+Cc: Russell King <linux@arm.linux.org.uk>
+Cc: Courtney Cavin <courtney.cavin@sonymobile.com>
+Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
+
+---
+arch/arm/common/Kconfig | 3 ++
+ arch/arm/common/Makefile | 1 +
+ arch/arm/common/krait-l2-accessors.c | 58 +++++++++++++++++++++++++++++++
+ arch/arm/include/asm/krait-l2-accessors.h | 20 +++++++++++
+ 4 files changed, 82 insertions(+)
+ create mode 100644 arch/arm/common/krait-l2-accessors.c
+ create mode 100644 arch/arm/include/asm/krait-l2-accessors.h
+
+--- a/arch/arm/common/Kconfig
++++ b/arch/arm/common/Kconfig
+@@ -9,6 +9,9 @@ config DMABOUNCE
+ bool
+ select ZONE_DMA
+
++config KRAIT_L2_ACCESSORS
++ bool
++
+ config SHARP_LOCOMO
+ bool
+
+--- a/arch/arm/common/Makefile
++++ b/arch/arm/common/Makefile
+@@ -7,6 +7,7 @@ obj-y += firmware.o
+ obj-$(CONFIG_ICST) += icst.o
+ obj-$(CONFIG_SA1111) += sa1111.o
+ obj-$(CONFIG_DMABOUNCE) += dmabounce.o
++obj-$(CONFIG_KRAIT_L2_ACCESSORS) += krait-l2-accessors.o
+ obj-$(CONFIG_SHARP_LOCOMO) += locomo.o
+ obj-$(CONFIG_SHARP_PARAM) += sharpsl_param.o
+ obj-$(CONFIG_SHARP_SCOOP) += scoop.o
+--- /dev/null
++++ b/arch/arm/common/krait-l2-accessors.c
+@@ -0,0 +1,58 @@
++/*
++ * Copyright (c) 2011-2013, The Linux Foundation. All rights reserved.
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 and
++ * only version 2 as published by the Free Software Foundation.
++ *
++ * 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/spinlock.h>
++#include <linux/export.h>
++
++#include <asm/barrier.h>
++#include <asm/krait-l2-accessors.h>
++
++static DEFINE_RAW_SPINLOCK(krait_l2_lock);
++
++void krait_set_l2_indirect_reg(u32 addr, u32 val)
++{
++ unsigned long flags;
++
++ raw_spin_lock_irqsave(&krait_l2_lock, flags);
++ /*
++ * Select the L2 window by poking l2cpselr, then write to the window
++ * via l2cpdr.
++ */
++ asm volatile ("mcr p15, 3, %0, c15, c0, 6 @ l2cpselr" : : "r" (addr));
++ isb();
++ asm volatile ("mcr p15, 3, %0, c15, c0, 7 @ l2cpdr" : : "r" (val));
++ isb();
++
++ raw_spin_unlock_irqrestore(&krait_l2_lock, flags);
++}
++EXPORT_SYMBOL(krait_set_l2_indirect_reg);
++
++u32 krait_get_l2_indirect_reg(u32 addr)
++{
++ u32 val;
++ unsigned long flags;
++
++ raw_spin_lock_irqsave(&krait_l2_lock, flags);
++ /*
++ * Select the L2 window by poking l2cpselr, then read from the window
++ * via l2cpdr.
++ */
++ asm volatile ("mcr p15, 3, %0, c15, c0, 6 @ l2cpselr" : : "r" (addr));
++ isb();
++ asm volatile ("mrc p15, 3, %0, c15, c0, 7 @ l2cpdr" : "=r" (val));
++
++ raw_spin_unlock_irqrestore(&krait_l2_lock, flags);
++
++ return val;
++}
++EXPORT_SYMBOL(krait_get_l2_indirect_reg);
+--- /dev/null
++++ b/arch/arm/include/asm/krait-l2-accessors.h
+@@ -0,0 +1,20 @@
++/*
++ * Copyright (c) 2011-2013, The Linux Foundation. All rights reserved.
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 and
++ * only version 2 as published by the Free Software Foundation.
++ *
++ * 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.
++ */
++
++#ifndef __ASMARM_KRAIT_L2_ACCESSORS_H
++#define __ASMARM_KRAIT_L2_ACCESSORS_H
++
++extern void krait_set_l2_indirect_reg(u32 addr, u32 val);
++extern u32 krait_get_l2_indirect_reg(u32 addr);
++
++#endif
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