Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

Pull ARM development updates from Russell King:
 "Included in this update:

   - moving PSCI code from ARM64/ARM to drivers/

   - removal of some architecture internals from global kernel view

   - addition of software based "privileged no access" support using the
     old domains register to turn off the ability for kernel
     loads/stores to access userspace.  Only the proper accessors will
     be usable.

   - addition of early fixup support for early console

   - re-addition (and reimplementation) of OMAP special interconnect
     barrier

   - removal of finish_arch_switch()

   - only expose cpuX/online in sysfs if hotpluggable

   - a number of code cleanups"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (41 commits)
  ARM: software-based priviledged-no-access support
  ARM: entry: provide uaccess assembly macro hooks
  ARM: entry: get rid of multiple macro definitions
  ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die()
  ARM: uaccess: provide uaccess_save_and_enable() and uaccess_restore()
  ARM: mm: improve do_ldrd_abort macro
  ARM: entry: ensure that IRQs are enabled when calling syscall_trace_exit()
  ARM: entry: efficiency cleanups
  ARM: entry: get rid of asm_trace_hardirqs_on_cond
  ARM: uaccess: simplify user access assembly
  ARM: domains: remove DOMAIN_TABLE
  ARM: domains: keep vectors in separate domain
  ARM: domains: get rid of manager mode for user domain
  ARM: domains: move initial domain setting value to asm/domains.h
  ARM: domains: provide domain_mask()
  ARM: domains: switch to keeping domain value in register
  ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE
  ARM: 8417/1: refactor bitops functions with BIT_MASK() and BIT_WORD()
  ARM: 8416/1: Feroceon: use of_iomap() to map register base
  ARM: 8415/1: early fixmap support for earlycon
  ...

arch/arm/mach-omap2/Kconfig

@@ -29,6 +29,7 @@ config ARCH_OMAP4
 	select HAVE_ARM_SCU if SMP
 	select HAVE_ARM_TWD if SMP
 	select OMAP_INTERCONNECT
+	select OMAP_INTERCONNECT_BARRIER
 	select PL310_ERRATA_588369 if CACHE_L2X0
 	select PL310_ERRATA_727915 if CACHE_L2X0
 	select PM_OPP if PM
@@ -46,6 +47,7 @@ config SOC_OMAP5
 	select HAVE_ARM_TWD if SMP
 	select HAVE_ARM_ARCH_TIMER
 	select ARM_ERRATA_798181 if SMP
+	select OMAP_INTERCONNECT_BARRIER
 
 config SOC_AM33XX
 	bool "TI AM33XX"
@@ -71,6 +73,7 @@ config SOC_DRA7XX
 	select HAVE_ARM_ARCH_TIMER
 	select IRQ_CROSSBAR
 	select ARM_ERRATA_798181 if SMP
+	select OMAP_INTERCONNECT_BARRIER
 
 config ARCH_OMAP2PLUS
 	bool
@@ -92,6 +95,10 @@ config ARCH_OMAP2PLUS
 	help
 	  Systems based on OMAP2, OMAP3, OMAP4 or OMAP5
 
+config OMAP_INTERCONNECT_BARRIER
+	bool
+	select ARM_HEAVY_MB
+	
 
 if ARCH_OMAP2PLUS
 

arch/arm/mach-omap2/common.c

@@ -30,4 +30,5 @@ int __weak omap_secure_ram_reserve_memblock(void)
 void __init omap_reserve(void)
 {
 	omap_secure_ram_reserve_memblock();
+	omap_barrier_reserve_memblock();
 }

arch/arm/mach-omap2/common.h

@@ -189,6 +189,15 @@ static inline void omap44xx_restart(enum reboot_mode mode, const char *cmd)
 }
 #endif
 
+#ifdef CONFIG_OMAP_INTERCONNECT_BARRIER
+void omap_barrier_reserve_memblock(void);
+void omap_barriers_init(void);
+#else
+static inline void omap_barrier_reserve_memblock(void)
+{
+}
+#endif
+
 /* This gets called from mach-omap2/io.c, do not call this */
 void __init omap2_set_globals_tap(u32 class, void __iomem *tap);
 

arch/arm/mach-omap2/include/mach/barriers.h

@@ -1,33 +0,0 @@
-/*
- * OMAP memory barrier header.
- *
- * Copyright (C) 2011 Texas Instruments, Inc.
- *  Santosh Shilimkar <santosh.shilimkar@ti.com>
- *  Richard Woodruff <r-woodruff2@ti.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-#ifndef __MACH_BARRIERS_H
-#define __MACH_BARRIERS_H
-
-#include <asm/outercache.h>
-
-extern void omap_bus_sync(void);
-
-#define rmb()		dsb()
-#define wmb()		do { dsb(); outer_sync(); omap_bus_sync(); } while (0)
-#define mb()		wmb()
-
-#endif	/* __MACH_BARRIERS_H */

arch/arm/mach-omap2/io.c

@@ -352,6 +352,7 @@ void __init am33xx_map_io(void)
 void __init omap4_map_io(void)
 {
 	iotable_init(omap44xx_io_desc, ARRAY_SIZE(omap44xx_io_desc));
+	omap_barriers_init();
 }
 #endif
 
@@ -359,6 +360,7 @@ void __init omap4_map_io(void)
 void __init omap5_map_io(void)
 {
 	iotable_init(omap54xx_io_desc, ARRAY_SIZE(omap54xx_io_desc));
+	omap_barriers_init();
 }
 #endif
 

arch/arm/mach-omap2/omap4-common.c

@@ -51,6 +51,127 @@ static void __iomem *twd_base;
 
 #define IRQ_LOCALTIMER		29
 
+#ifdef CONFIG_OMAP_INTERCONNECT_BARRIER
+
+/* Used to implement memory barrier on DRAM path */
+#define OMAP4_DRAM_BARRIER_VA			0xfe600000
+
+static void __iomem *dram_sync, *sram_sync;
+static phys_addr_t dram_sync_paddr;
+static u32 dram_sync_size;
+
+/*
+ * The OMAP4 bus structure contains asynchrnous bridges which can buffer
+ * data writes from the MPU. These asynchronous bridges can be found on
+ * paths between the MPU to EMIF, and the MPU to L3 interconnects.
+ *
+ * We need to be careful about re-ordering which can happen as a result
+ * of different accesses being performed via different paths, and
+ * therefore different asynchronous bridges.
+ */
+
+/*
+ * OMAP4 interconnect barrier which is called for each mb() and wmb().
+ * This is to ensure that normal paths to DRAM (normal memory, cacheable
+ * accesses) are properly synchronised with writes to DMA coherent memory
+ * (normal memory, uncacheable) and device writes.
+ *
+ * The mb() and wmb() barriers only operate only on the MPU->MA->EMIF
+ * path, as we need to ensure that data is visible to other system
+ * masters prior to writes to those system masters being seen.
+ *
+ * Note: the SRAM path is not synchronised via mb() and wmb().
+ */
+static void omap4_mb(void)
+{
+	if (dram_sync)
+		writel_relaxed(0, dram_sync);
+}
+
+/*
+ * OMAP4 Errata i688 - asynchronous bridge corruption when entering WFI.
+ *
+ * If a data is stalled inside asynchronous bridge because of back
+ * pressure, it may be accepted multiple times, creating pointer
+ * misalignment that will corrupt next transfers on that data path until
+ * next reset of the system. No recovery procedure once the issue is hit,
+ * the path remains consistently broken.
+ *
+ * Async bridges can be found on paths between MPU to EMIF and MPU to L3
+ * interconnects.
+ *
+ * This situation can happen only when the idle is initiated by a Master
+ * Request Disconnection (which is trigged by software when executing WFI
+ * on the CPU).
+ *
+ * The work-around for this errata needs all the initiators connected
+ * through an async bridge to ensure that data path is properly drained
+ * before issuing WFI. This condition will be met if one Strongly ordered
+ * access is performed to the target right before executing the WFI.
+ *
+ * In MPU case, L3 T2ASYNC FIFO and DDR T2ASYNC FIFO needs to be drained.
+ * IO barrier ensure that there is no synchronisation loss on initiators
+ * operating on both interconnect port simultaneously.
+ *
+ * This is a stronger version of the OMAP4 memory barrier below, and
+ * operates on both the MPU->MA->EMIF path but also the MPU->OCP path
+ * as well, and is necessary prior to executing a WFI.
+ */
+void omap_interconnect_sync(void)
+{
+	if (dram_sync && sram_sync) {
+		writel_relaxed(readl_relaxed(dram_sync), dram_sync);
+		writel_relaxed(readl_relaxed(sram_sync), sram_sync);
+		isb();
+	}
+}
+
+static int __init omap4_sram_init(void)
+{
+	struct device_node *np;
+	struct gen_pool *sram_pool;
+
+	np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
+	if (!np)
+		pr_warn("%s:Unable to allocate sram needed to handle errata I688\n",
+			__func__);
+	sram_pool = of_gen_pool_get(np, "sram", 0);
+	if (!sram_pool)
+		pr_warn("%s:Unable to get sram pool needed to handle errata I688\n",
+			__func__);
+	else
+		sram_sync = (void *)gen_pool_alloc(sram_pool, PAGE_SIZE);
+
+	return 0;
+}
+omap_arch_initcall(omap4_sram_init);
+
+/* Steal one page physical memory for barrier implementation */
+void __init omap_barrier_reserve_memblock(void)
+{
+	dram_sync_size = ALIGN(PAGE_SIZE, SZ_1M);
+	dram_sync_paddr = arm_memblock_steal(dram_sync_size, SZ_1M);
+}
+
+void __init omap_barriers_init(void)
+{
+	struct map_desc dram_io_desc[1];
+
+	dram_io_desc[0].virtual = OMAP4_DRAM_BARRIER_VA;
+	dram_io_desc[0].pfn = __phys_to_pfn(dram_sync_paddr);
+	dram_io_desc[0].length = dram_sync_size;
+	dram_io_desc[0].type = MT_MEMORY_RW_SO;
+	iotable_init(dram_io_desc, ARRAY_SIZE(dram_io_desc));
+	dram_sync = (void __iomem *) dram_io_desc[0].virtual;
+
+	pr_info("OMAP4: Map %pa to %p for dram barrier\n",
+		&dram_sync_paddr, dram_sync);
+
+	soc_mb = omap4_mb;
+}
+
+#endif
+
 void gic_dist_disable(void)
 {
 	if (gic_dist_base_addr)

arch/arm/mach-omap2/sleep44xx.S

@@ -333,14 +333,12 @@ ENDPROC(omap4_cpu_resume)
 
 #endif	/* defined(CONFIG_SMP) && defined(CONFIG_PM) */
 
-ENTRY(omap_bus_sync)
-	ret	lr
-ENDPROC(omap_bus_sync)
-
 ENTRY(omap_do_wfi)
 	stmfd	sp!, {lr}
+#ifdef CONFIG_OMAP_INTERCONNECT_BARRIER
 	/* Drain interconnect write buffers. */
-	bl omap_bus_sync
+	bl	omap_interconnect_sync
+#endif
 
 	/*
 	 * Execute an ISB instruction to ensure that all of the