AArch32: Add assembly helpers
This patch adds various assembly helpers for AArch32 like :
* cache management : Functions to flush, invalidate and clean
cache by MVA. Also helpers to do cache operations by set-way
are also added.
* stack management: Macros to declare stack and get the current
stack corresponding to current CPU.
* Misc: Macros to access co processor registers in AArch32,
macros to define functions in assembly, assert macros, generic
`do_panic()` implementation and function to zero block of memory.
Change-Id: I7b78ca3f922c0eda39beb9786b7150e9193425be
diff --git a/lib/aarch32/cache_helpers.S b/lib/aarch32/cache_helpers.S
new file mode 100644
index 0000000..d0e5cd0
--- /dev/null
+++ b/lib/aarch32/cache_helpers.S
@@ -0,0 +1,237 @@
+/*
+ * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+
+ .globl flush_dcache_range
+ .globl clean_dcache_range
+ .globl inv_dcache_range
+ .globl dcsw_op_louis
+ .globl dcsw_op_all
+ .globl dcsw_op_level1
+ .globl dcsw_op_level2
+ .globl dcsw_op_level3
+
+/*
+ * This macro can be used for implementing various data cache operations `op`
+ */
+.macro do_dcache_maintenance_by_mva op, coproc, opc1, CRn, CRm, opc2
+ dcache_line_size r2, r3
+ add r1, r0, r1
+ sub r3, r2, #1
+ bic r0, r0, r3
+loop_\op:
+ stcopr r0, \coproc, \opc1, \CRn, \CRm, \opc2
+ add r0, r0, r2
+ cmp r0, r1
+ blo loop_\op
+ dsb sy
+ bx lr
+.endm
+
+ /* ------------------------------------------
+ * Clean+Invalidate from base address till
+ * size. 'r0' = addr, 'r1' = size
+ * ------------------------------------------
+ */
+func flush_dcache_range
+ do_dcache_maintenance_by_mva cimvac, DCCIMVAC
+endfunc flush_dcache_range
+
+ /* ------------------------------------------
+ * Clean from base address till size.
+ * 'r0' = addr, 'r1' = size
+ * ------------------------------------------
+ */
+func clean_dcache_range
+ do_dcache_maintenance_by_mva cmvac, DCCMVAC
+endfunc clean_dcache_range
+
+ /* ------------------------------------------
+ * Invalidate from base address till
+ * size. 'r0' = addr, 'r1' = size
+ * ------------------------------------------
+ */
+func inv_dcache_range
+ do_dcache_maintenance_by_mva imvac, DCIMVAC
+endfunc inv_dcache_range
+
+ /* ----------------------------------------------------------------
+ * Data cache operations by set/way to the level specified
+ *
+ * The main function, do_dcsw_op requires:
+ * r0: The operation type (DC_OP_ISW, DC_OP_CISW, DC_OP_CSW),
+ * as defined in arch.h
+ * r1: The cache level to begin operation from
+ * r2: clidr_el1
+ * r3: The last cache level to operate on
+ * and will carry out the operation on each data cache from level 0
+ * to the level in r3 in sequence
+ *
+ * The dcsw_op macro sets up the r2 and r3 parameters based on
+ * clidr_el1 cache information before invoking the main function
+ * ----------------------------------------------------------------
+ */
+
+ .macro dcsw_op shift, fw, ls
+ ldcopr r2, CLIDR
+ ubfx r3, r2, \shift, \fw
+ lsl r3, r3, \ls
+ mov r1, #0
+ b do_dcsw_op
+ .endm
+
+func do_dcsw_op
+ push {r4-r12,lr}
+ adr r11, dcsw_loop_table // compute cache op based on the operation type
+ add r6, r11, r0, lsl #3 // cache op is 2x32-bit instructions
+loop1:
+ add r10, r1, r1, LSR #1 // Work out 3x current cache level
+ mov r12, r2, LSR r10 // extract cache type bits from clidr
+ and r12, r12, #7 // mask the bits for current cache only
+ cmp r12, #2 // see what cache we have at this level
+ blt level_done // no cache or only instruction cache at this level
+
+ stcopr r1, CSSELR // select current cache level in csselr
+ isb // isb to sych the new cssr&csidr
+ ldcopr r12, CCSIDR // read the new ccsidr
+ and r10, r12, #7 // extract the length of the cache lines
+ add r10, r10, #4 // add 4 (r10 = line length offset)
+ ubfx r4, r12, #3, #10 // r4 = maximum way number (right aligned)
+ clz r5, r4 // r5 = the bit position of the way size increment
+ mov r9, r4 // r9 working copy of the aligned max way number
+
+loop2:
+ ubfx r7, r12, #13, #15 // r7 = max set number (right aligned)
+
+loop3:
+ orr r0, r1, r9, LSL r5 // factor in the way number and cache level into r0
+ orr r0, r0, r7, LSL r10 // factor in the set number
+
+ blx r6
+ subs r7, r7, #1 // decrement the set number
+ bge loop3
+ subs r9, r9, #1 // decrement the way number
+ bge loop2
+level_done:
+ add r1, r1, #2 // increment the cache number
+ cmp r3, r1
+ dsb sy // ensure completion of previous cache maintenance instruction
+ bgt loop1
+
+ mov r6, #0
+ stcopr r6, CSSELR //select cache level 0 in csselr
+ dsb sy
+ isb
+ pop {r4-r12,pc}
+
+dcsw_loop_table:
+ stcopr r0, DCISW
+ bx lr
+ stcopr r0, DCCISW
+ bx lr
+ stcopr r0, DCCSW
+ bx lr
+
+endfunc do_dcsw_op
+
+ /* ---------------------------------------------------------------
+ * Data cache operations by set/way till PoU.
+ *
+ * The function requires :
+ * r0: The operation type (DC_OP_ISW, DC_OP_CISW, DC_OP_CSW),
+ * as defined in arch.h
+ * ---------------------------------------------------------------
+ */
+func dcsw_op_louis
+ dcsw_op #LOUIS_SHIFT, #CLIDR_FIELD_WIDTH, #LEVEL_SHIFT
+endfunc dcsw_op_louis
+
+ /* ---------------------------------------------------------------
+ * Data cache operations by set/way till PoC.
+ *
+ * The function requires :
+ * r0: The operation type (DC_OP_ISW, DC_OP_CISW, DC_OP_CSW),
+ * as defined in arch.h
+ * ---------------------------------------------------------------
+ */
+func dcsw_op_all
+ dcsw_op #LOC_SHIFT, #CLIDR_FIELD_WIDTH, #LEVEL_SHIFT
+endfunc dcsw_op_all
+
+
+ /* ---------------------------------------------------------------
+ * Helper macro for data cache operations by set/way for the
+ * level specified
+ * ---------------------------------------------------------------
+ */
+ .macro dcsw_op_level level
+ ldcopr r2, CLIDR
+ mov r3, \level
+ sub r1, r3, #2
+ b do_dcsw_op
+ .endm
+
+ /* ---------------------------------------------------------------
+ * Data cache operations by set/way for level 1 cache
+ *
+ * The main function, do_dcsw_op requires:
+ * r0: The operation type (DC_OP_ISW, DC_OP_CISW, DC_OP_CSW),
+ * as defined in arch.h
+ * ---------------------------------------------------------------
+ */
+func dcsw_op_level1
+ dcsw_op_level #(1 << LEVEL_SHIFT)
+endfunc dcsw_op_level1
+
+ /* ---------------------------------------------------------------
+ * Data cache operations by set/way for level 2 cache
+ *
+ * The main function, do_dcsw_op requires:
+ * r0: The operation type (DC_OP_ISW, DC_OP_CISW, DC_OP_CSW),
+ * as defined in arch.h
+ * ---------------------------------------------------------------
+ */
+func dcsw_op_level2
+ dcsw_op_level #(2 << LEVEL_SHIFT)
+endfunc dcsw_op_level2
+
+ /* ---------------------------------------------------------------
+ * Data cache operations by set/way for level 3 cache
+ *
+ * The main function, do_dcsw_op requires:
+ * r0: The operation type (DC_OP_ISW, DC_OP_CISW, DC_OP_CSW),
+ * as defined in arch.h
+ * ---------------------------------------------------------------
+ */
+func dcsw_op_level3
+ dcsw_op_level #(3 << LEVEL_SHIFT)
+endfunc dcsw_op_level3