--- /dev/null
+/*
+ * 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.
+ */
+
+#ifndef __MIPS_ASM_MIPS_CM_H__
+#define __MIPS_ASM_MIPS_CM_H__
+
+#include <linux/io.h>
+#include <linux/types.h>
+
+/* The base address of the CM GCR block */
+extern void __iomem *mips_cm_base;
+
+/* The base address of the CM L2-only sync region */
+extern void __iomem *mips_cm_l2sync_base;
+
+/**
+ * __mips_cm_phys_base - retrieve the physical base address of the CM
+ *
+ * This function returns the physical base address of the Coherence Manager
+ * global control block, or 0 if no Coherence Manager is present. It provides
+ * a default implementation which reads the CMGCRBase register where available,
+ * and may be overriden by platforms which determine this address in a
+ * different way by defining a function with the same prototype except for the
+ * name mips_cm_phys_base (without underscores).
+ */
+extern phys_t __mips_cm_phys_base(void);
+
+/**
+ * mips_cm_probe - probe for a Coherence Manager
+ *
+ * Attempt to detect the presence of a Coherence Manager. Returns 0 if a CM
+ * is successfully detected, else -errno.
+ */
+#ifdef CONFIG_MIPS_CM
+extern int mips_cm_probe(void);
+#else
+static inline int mips_cm_probe(void)
+{
+       return -ENODEV;
+}
+#endif
+
+/**
+ * mips_cm_present - determine whether a Coherence Manager is present
+ *
+ * Returns true if a CM is present in the system, else false.
+ */
+static inline bool mips_cm_present(void)
+{
+#ifdef CONFIG_MIPS_CM
+       return mips_cm_base != NULL;
+#else
+       return false;
+#endif
+}
+
+/**
+ * mips_cm_has_l2sync - determine whether an L2-only sync region is present
+ *
+ * Returns true if the system implements an L2-only sync region, else false.
+ */
+static inline bool mips_cm_has_l2sync(void)
+{
+#ifdef CONFIG_MIPS_CM
+       return mips_cm_l2sync_base != NULL;
+#else
+       return false;
+#endif
+}
+
+/* Offsets to register blocks from the CM base address */
+#define MIPS_CM_GCB_OFS                0x0000 /* Global Control Block */
+#define MIPS_CM_CLCB_OFS       0x2000 /* Core Local Control Block */
+#define MIPS_CM_COCB_OFS       0x4000 /* Core Other Control Block */
+#define MIPS_CM_GDB_OFS                0x6000 /* Global Debug Block */
+
+/* Total size of the CM memory mapped registers */
+#define MIPS_CM_GCR_SIZE       0x8000
+
+/* Size of the L2-only sync region */
+#define MIPS_CM_L2SYNC_SIZE    0x1000
+
+/* Macros to ease the creation of register access functions */
+#define BUILD_CM_R_(name, off)                                 \
+static inline u32 *addr_gcr_##name(void)                       \
+{                                                              \
+       return (u32 *)(mips_cm_base + (off));                   \
+}                                                              \
+                                                               \
+static inline u32 read_gcr_##name(void)                                \
+{                                                              \
+       return readl(addr_gcr_##name());                        \
+}
+
+#define BUILD_CM__W(name, off)                                 \
+static inline void write_gcr_##name(u32 value)                 \
+{                                                              \
+       writel(value, addr_gcr_##name());                       \
+}
+
+#define BUILD_CM_RW(name, off)                                 \
+       BUILD_CM_R_(name, off)                                  \
+       BUILD_CM__W(name, off)
+
+#define BUILD_CM_Cx_R_(name, off)                              \
+       BUILD_CM_R_(cl_##name, MIPS_CM_CLCB_OFS + (off))        \
+       BUILD_CM_R_(co_##name, MIPS_CM_COCB_OFS + (off))
+
+#define BUILD_CM_Cx__W(name, off)                              \
+       BUILD_CM__W(cl_##name, MIPS_CM_CLCB_OFS + (off))        \
+       BUILD_CM__W(co_##name, MIPS_CM_COCB_OFS + (off))
+
+#define BUILD_CM_Cx_RW(name, off)                              \
+       BUILD_CM_Cx_R_(name, off)                               \
+       BUILD_CM_Cx__W(name, off)
+
+/* GCB register accessor functions */
+BUILD_CM_R_(config,            MIPS_CM_GCB_OFS + 0x00)
+BUILD_CM_RW(base,              MIPS_CM_GCB_OFS + 0x08)
+BUILD_CM_RW(access,            MIPS_CM_GCB_OFS + 0x20)
+BUILD_CM_R_(rev,               MIPS_CM_GCB_OFS + 0x30)
+BUILD_CM_RW(error_mask,                MIPS_CM_GCB_OFS + 0x40)
+BUILD_CM_RW(error_cause,       MIPS_CM_GCB_OFS + 0x48)
+BUILD_CM_RW(error_addr,                MIPS_CM_GCB_OFS + 0x50)
+BUILD_CM_RW(error_mult,                MIPS_CM_GCB_OFS + 0x58)
+BUILD_CM_RW(l2_only_sync_base, MIPS_CM_GCB_OFS + 0x70)
+BUILD_CM_RW(gic_base,          MIPS_CM_GCB_OFS + 0x80)
+BUILD_CM_RW(cpc_base,          MIPS_CM_GCB_OFS + 0x88)
+BUILD_CM_RW(reg0_base,         MIPS_CM_GCB_OFS + 0x90)
+BUILD_CM_RW(reg0_mask,         MIPS_CM_GCB_OFS + 0x98)
+BUILD_CM_RW(reg1_base,         MIPS_CM_GCB_OFS + 0xa0)
+BUILD_CM_RW(reg1_mask,         MIPS_CM_GCB_OFS + 0xa8)
+BUILD_CM_RW(reg2_base,         MIPS_CM_GCB_OFS + 0xb0)
+BUILD_CM_RW(reg2_mask,         MIPS_CM_GCB_OFS + 0xb8)
+BUILD_CM_RW(reg3_base,         MIPS_CM_GCB_OFS + 0xc0)
+BUILD_CM_RW(reg3_mask,         MIPS_CM_GCB_OFS + 0xc8)
+BUILD_CM_R_(gic_status,                MIPS_CM_GCB_OFS + 0xd0)
+BUILD_CM_R_(cpc_status,                MIPS_CM_GCB_OFS + 0xf0)
+
+/* Core Local & Core Other register accessor functions */
+BUILD_CM_Cx_RW(reset_release,  0x00)
+BUILD_CM_Cx_RW(coherence,      0x08)
+BUILD_CM_Cx_R_(config,         0x10)
+BUILD_CM_Cx_RW(other,          0x18)
+BUILD_CM_Cx_RW(reset_base,     0x20)
+BUILD_CM_Cx_R_(id,             0x28)
+BUILD_CM_Cx_RW(reset_ext_base, 0x30)
+BUILD_CM_Cx_R_(tcid_0_priority,        0x40)
+BUILD_CM_Cx_R_(tcid_1_priority,        0x48)
+BUILD_CM_Cx_R_(tcid_2_priority,        0x50)
+BUILD_CM_Cx_R_(tcid_3_priority,        0x58)
+BUILD_CM_Cx_R_(tcid_4_priority,        0x60)
+BUILD_CM_Cx_R_(tcid_5_priority,        0x68)
+BUILD_CM_Cx_R_(tcid_6_priority,        0x70)
+BUILD_CM_Cx_R_(tcid_7_priority,        0x78)
+BUILD_CM_Cx_R_(tcid_8_priority,        0x80)
+
+/* GCR_CONFIG register fields */
+#define CM_GCR_CONFIG_NUMIOCU_SHF              8
+#define CM_GCR_CONFIG_NUMIOCU_MSK              (_ULCAST_(0xf) << 8)
+#define CM_GCR_CONFIG_PCORES_SHF               0
+#define CM_GCR_CONFIG_PCORES_MSK               (_ULCAST_(0xff) << 0)
+
+/* GCR_BASE register fields */
+#define CM_GCR_BASE_GCRBASE_SHF                        15
+#define CM_GCR_BASE_GCRBASE_MSK                        (_ULCAST_(0x1ffff) << 15)
+#define CM_GCR_BASE_CMDEFTGT_SHF               0
+#define CM_GCR_BASE_CMDEFTGT_MSK               (_ULCAST_(0x3) << 0)
+#define  CM_GCR_BASE_CMDEFTGT_DISABLED         0
+#define  CM_GCR_BASE_CMDEFTGT_MEM              1
+#define  CM_GCR_BASE_CMDEFTGT_IOCU0            2
+#define  CM_GCR_BASE_CMDEFTGT_IOCU1            3
+
+/* GCR_ACCESS register fields */
+#define CM_GCR_ACCESS_ACCESSEN_SHF             0
+#define CM_GCR_ACCESS_ACCESSEN_MSK             (_ULCAST_(0xff) << 0)
+
+/* GCR_REV register fields */
+#define CM_GCR_REV_MAJOR_SHF                   8
+#define CM_GCR_REV_MAJOR_MSK                   (_ULCAST_(0xff) << 8)
+#define CM_GCR_REV_MINOR_SHF                   0
+#define CM_GCR_REV_MINOR_MSK                   (_ULCAST_(0xff) << 0)
+
+/* GCR_ERROR_CAUSE register fields */
+#define CM_GCR_ERROR_CAUSE_ERRTYPE_SHF         27
+#define CM_GCR_ERROR_CAUSE_ERRTYPE_MSK         (_ULCAST_(0x1f) << 27)
+#define CM_GCR_ERROR_CAUSE_ERRINFO_SHF         0
+#define CM_GCR_ERROR_CAUSE_ERRINGO_MSK         (_ULCAST_(0x7ffffff) << 0)
+
+/* GCR_ERROR_MULT register fields */
+#define CM_GCR_ERROR_MULT_ERR2ND_SHF           0
+#define CM_GCR_ERROR_MULT_ERR2ND_MSK           (_ULCAST_(0x1f) << 0)
+
+/* GCR_L2_ONLY_SYNC_BASE register fields */
+#define CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE_SHF  12
+#define CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE_MSK  (_ULCAST_(0xfffff) << 12)
+#define CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN_SHF    0
+#define CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN_MSK    (_ULCAST_(0x1) << 0)
+
+/* GCR_GIC_BASE register fields */
+#define CM_GCR_GIC_BASE_GICBASE_SHF            17
+#define CM_GCR_GIC_BASE_GICBASE_MSK            (_ULCAST_(0x7fff) << 17)
+#define CM_GCR_GIC_BASE_GICEN_SHF              0
+#define CM_GCR_GIC_BASE_GICEN_MSK              (_ULCAST_(0x1) << 0)
+
+/* GCR_CPC_BASE register fields */
+#define CM_GCR_CPC_BASE_CPCBASE_SHF            17
+#define CM_GCR_CPC_BASE_CPCBASE_MSK            (_ULCAST_(0x7fff) << 17)
+#define CM_GCR_CPC_BASE_CPCEN_SHF              0
+#define CM_GCR_CPC_BASE_CPCEN_MSK              (_ULCAST_(0x1) << 0)
+
+/* GCR_REGn_BASE register fields */
+#define CM_GCR_REGn_BASE_BASEADDR_SHF          16
+#define CM_GCR_REGn_BASE_BASEADDR_MSK          (_ULCAST_(0xffff) << 16)
+
+/* GCR_REGn_MASK register fields */
+#define CM_GCR_REGn_MASK_ADDRMASK_SHF          16
+#define CM_GCR_REGn_MASK_ADDRMASK_MSK          (_ULCAST_(0xffff) << 16)
+#define CM_GCR_REGn_MASK_CCAOVR_SHF            5
+#define CM_GCR_REGn_MASK_CCAOVR_MSK            (_ULCAST_(0x3) << 5)
+#define CM_GCR_REGn_MASK_CCAOVREN_SHF          4
+#define CM_GCR_REGn_MASK_CCAOVREN_MSK          (_ULCAST_(0x1) << 4)
+#define CM_GCR_REGn_MASK_DROPL2_SHF            2
+#define CM_GCR_REGn_MASK_DROPL2_MSK            (_ULCAST_(0x1) << 2)
+#define CM_GCR_REGn_MASK_CMTGT_SHF             0
+#define CM_GCR_REGn_MASK_CMTGT_MSK             (_ULCAST_(0x3) << 0)
+#define  CM_GCR_REGn_MASK_CMTGT_DISABLED       (_ULCAST_(0x0) << 0)
+#define  CM_GCR_REGn_MASK_CMTGT_MEM            (_ULCAST_(0x1) << 0)
+#define  CM_GCR_REGn_MASK_CMTGT_IOCU0          (_ULCAST_(0x2) << 0)
+#define  CM_GCR_REGn_MASK_CMTGT_IOCU1          (_ULCAST_(0x3) << 0)
+
+/* GCR_GIC_STATUS register fields */
+#define CM_GCR_GIC_STATUS_EX_SHF               0
+#define CM_GCR_GIC_STATUS_EX_MSK               (_ULCAST_(0x1) << 0)
+
+/* GCR_CPC_STATUS register fields */
+#define CM_GCR_CPC_STATUS_EX_SHF               0
+#define CM_GCR_CPC_STATUS_EX_MSK               (_ULCAST_(0x1) << 0)
+
+/* GCR_Cx_COHERENCE register fields */
+#define CM_GCR_Cx_COHERENCE_COHDOMAINEN_SHF    0
+#define CM_GCR_Cx_COHERENCE_COHDOMAINEN_MSK    (_ULCAST_(0xff) << 0)
+
+/* GCR_Cx_CONFIG register fields */
+#define CM_GCR_Cx_CONFIG_IOCUTYPE_SHF          10
+#define CM_GCR_Cx_CONFIG_IOCUTYPE_MSK          (_ULCAST_(0x3) << 10)
+#define CM_GCR_Cx_CONFIG_PVPE_SHF              0
+#define CM_GCR_Cx_CONFIG_PVPE_MSK              (_ULCAST_(0x1ff) << 0)
+
+/* GCR_Cx_OTHER register fields */
+#define CM_GCR_Cx_OTHER_CORENUM_SHF            16
+#define CM_GCR_Cx_OTHER_CORENUM_MSK            (_ULCAST_(0xffff) << 16)
+
+/* GCR_Cx_RESET_BASE register fields */
+#define CM_GCR_Cx_RESET_BASE_BEVEXCBASE_SHF    12
+#define CM_GCR_Cx_RESET_BASE_BEVEXCBASE_MSK    (_ULCAST_(0xfffff) << 12)
+
+/* GCR_Cx_RESET_EXT_BASE register fields */
+#define CM_GCR_Cx_RESET_EXT_BASE_EVARESET_SHF  31
+#define CM_GCR_Cx_RESET_EXT_BASE_EVARESET_MSK  (_ULCAST_(0x1) << 31)
+#define CM_GCR_Cx_RESET_EXT_BASE_UEB_SHF       30
+#define CM_GCR_Cx_RESET_EXT_BASE_UEB_MSK       (_ULCAST_(0x1) << 30)
+#define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCMASK_SHF        20
+#define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCMASK_MSK        (_ULCAST_(0xff) << 20)
+#define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCPA_SHF  1
+#define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCPA_MSK  (_ULCAST_(0x7f) << 1)
+#define CM_GCR_Cx_RESET_EXT_BASE_PRESENT_SHF   0
+#define CM_GCR_Cx_RESET_EXT_BASE_PRESENT_MSK   (_ULCAST_(0x1) << 0)
+
+/**
+ * mips_cm_numcores - return the number of cores present in the system
+ *
+ * Returns the value of the PCORES field of the GCR_CONFIG register plus 1, or
+ * zero if no Coherence Manager is present.
+ */
+static inline unsigned mips_cm_numcores(void)
+{
+       if (!mips_cm_present())
+               return 0;
+
+       return ((read_gcr_config() & CM_GCR_CONFIG_PCORES_MSK)
+               >> CM_GCR_CONFIG_PCORES_SHF) + 1;
+}
+
+/**
+ * mips_cm_numiocu - return the number of IOCUs present in the system
+ *
+ * Returns the value of the NUMIOCU field of the GCR_CONFIG register, or zero
+ * if no Coherence Manager is present.
+ */
+static inline unsigned mips_cm_numiocu(void)
+{
+       if (!mips_cm_present())
+               return 0;
+
+       return (read_gcr_config() & CM_GCR_CONFIG_NUMIOCU_MSK)
+               >> CM_GCR_CONFIG_NUMIOCU_SHF;
+}
+
+/**
+ * mips_cm_l2sync - perform an L2-only sync operation
+ *
+ * If an L2-only sync region is present in the system then this function
+ * performs and L2-only sync and returns zero. Otherwise it returns -ENODEV.
+ */
+static inline int mips_cm_l2sync(void)
+{
+       if (!mips_cm_has_l2sync())
+               return -ENODEV;
+
+       writel(0, mips_cm_l2sync_base);
+       return 0;
+}
+
+#endif /* __MIPS_ASM_MIPS_CM_H__ */
 
--- /dev/null
+/*
+ * 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 <asm/mips-cm.h>
+#include <asm/mipsregs.h>
+
+void __iomem *mips_cm_base;
+void __iomem *mips_cm_l2sync_base;
+
+phys_t __mips_cm_phys_base(void)
+{
+       u32 config3 = read_c0_config3();
+       u32 cmgcr;
+
+       /* Check the CMGCRBase register is implemented */
+       if (!(config3 & MIPS_CONF3_CMGCR))
+               return 0;
+
+       /* Read the address from CMGCRBase */
+       cmgcr = read_c0_cmgcrbase();
+       return (cmgcr & MIPS_CMGCRF_BASE) << (36 - 32);
+}
+
+phys_t mips_cm_phys_base(void)
+       __attribute__((weak, alias("__mips_cm_phys_base")));
+
+phys_t __mips_cm_l2sync_phys_base(void)
+{
+       u32 base_reg;
+
+       /*
+        * If the L2-only sync region is already enabled then leave it at it's
+        * current location.
+        */
+       base_reg = read_gcr_l2_only_sync_base();
+       if (base_reg & CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN_MSK)
+               return base_reg & CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE_MSK;
+
+       /* Default to following the CM */
+       return mips_cm_phys_base() + MIPS_CM_GCR_SIZE;
+}
+
+phys_t mips_cm_l2sync_phys_base(void)
+       __attribute__((weak, alias("__mips_cm_l2sync_phys_base")));
+
+static void mips_cm_probe_l2sync(void)
+{
+       unsigned major_rev;
+       phys_t addr;
+
+       /* L2-only sync was introduced with CM major revision 6 */
+       major_rev = (read_gcr_rev() & CM_GCR_REV_MAJOR_MSK) >>
+               CM_GCR_REV_MAJOR_SHF;
+       if (major_rev < 6)
+               return;
+
+       /* Find a location for the L2 sync region */
+       addr = mips_cm_l2sync_phys_base();
+       BUG_ON((addr & CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE_MSK) != addr);
+       if (!addr)
+               return;
+
+       /* Set the region base address & enable it */
+       write_gcr_l2_only_sync_base(addr | CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN_MSK);
+
+       /* Map the region */
+       mips_cm_l2sync_base = ioremap_nocache(addr, MIPS_CM_L2SYNC_SIZE);
+}
+
+int mips_cm_probe(void)
+{
+       phys_t addr;
+       u32 base_reg;
+
+       addr = mips_cm_phys_base();
+       BUG_ON((addr & CM_GCR_BASE_GCRBASE_MSK) != addr);
+       if (!addr)
+               return -ENODEV;
+
+       mips_cm_base = ioremap_nocache(addr, MIPS_CM_GCR_SIZE);
+       if (!mips_cm_base)
+               return -ENXIO;
+
+       /* sanity check that we're looking at a CM */
+       base_reg = read_gcr_base();
+       if ((base_reg & CM_GCR_BASE_GCRBASE_MSK) != addr) {
+               pr_err("GCRs appear to have been moved (expected them at 0x%08lx)!\n",
+                      (unsigned long)addr);
+               mips_cm_base = NULL;
+               return -ENODEV;
+       }
+
+       /* set default target to memory */
+       base_reg &= ~CM_GCR_BASE_CMDEFTGT_MSK;
+       base_reg |= CM_GCR_BASE_CMDEFTGT_MEM;
+       write_gcr_base(base_reg);
+
+       /* disable CM regions */
+       write_gcr_reg0_base(CM_GCR_REGn_BASE_BASEADDR_MSK);
+       write_gcr_reg0_mask(CM_GCR_REGn_MASK_ADDRMASK_MSK);
+       write_gcr_reg1_base(CM_GCR_REGn_BASE_BASEADDR_MSK);
+       write_gcr_reg1_mask(CM_GCR_REGn_MASK_ADDRMASK_MSK);
+       write_gcr_reg2_base(CM_GCR_REGn_BASE_BASEADDR_MSK);
+       write_gcr_reg2_mask(CM_GCR_REGn_MASK_ADDRMASK_MSK);
+       write_gcr_reg3_base(CM_GCR_REGn_BASE_BASEADDR_MSK);
+       write_gcr_reg3_mask(CM_GCR_REGn_MASK_ADDRMASK_MSK);
+
+       /* probe for an L2-only sync region */
+       mips_cm_probe_l2sync();
+
+       return 0;
+}