blob: ce41baeec673b7dac6e7f3381f0d7e2feb06dbdf [file] [log] [blame]
/*
* Copyright (c) 2013-2015, 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>
#include <bl_common.h>
#include <cortex_a57.h>
#include <v2m_def.h>
#include "../juno_def.h"
.globl plat_reset_handler
/* --------------------------------------------------------------------
* void plat_reset_handler(void);
*
* For Juno r0:
* - Implement workaround for defect id 831273 by enabling an event
* stream every 65536 cycles.
* - Set the L2 Data RAM latency to 2 (i.e. 3 cycles) for Cortex-A57
* - Set the L2 Tag RAM latency to 2 (i.e. 3 cycles) for Cortex-A57
*
* For Juno r1:
* - Set the L2 Data RAM latency to 2 (i.e. 3 cycles) for Cortex-A57
* Note that:
* - The default value for the L2 Tag RAM latency for Cortex-A57 is
* suitable.
* - Defect #831273 doesn't affect Juno r1.
* --------------------------------------------------------------------
*/
func plat_reset_handler
/* --------------------------------------------------------------------
* Determine whether this code is running on Juno r0 or Juno r1.
* Keep this information in x2.
* --------------------------------------------------------------------
*/
/* Read the V2M SYS_ID register */
mov_imm x0, (V2M_SYSREGS_BASE + V2M_SYS_ID)
ldr w1, [x0]
/* Extract board revision from the SYS_ID */
ubfx x1, x1, #V2M_SYS_ID_REV_SHIFT, #4
/*
* On Juno R0: x2 := REV_JUNO_R0 - 1 = 0
* On Juno R1: x2 := REV_JUNO_R1 - 1 = 1
*/
sub x2, x1, #1
/* --------------------------------------------------------------------
* Determine whether this code is executed on a Cortex-A53 or on a
* Cortex-A57 core.
* --------------------------------------------------------------------
*/
mrs x0, midr_el1
ubfx x1, x0, MIDR_PN_SHIFT, #12
cmp w1, #((CORTEX_A57_MIDR >> MIDR_PN_SHIFT) & MIDR_PN_MASK)
b.eq A57
/* Nothing needs to be done for the Cortex-A53 on Juno r1 */
cbz x2, apply_831273
ret
A57:
/* --------------------------------------------------------------------
* Cortex-A57 specific settings
* --------------------------------------------------------------------
*/
/* Change the L2 Data RAM latency to 3 cycles */
mov x0, #L2_DATA_RAM_LATENCY_3_CYCLES
cbnz x2, apply_l2_ram_latencies
/* On Juno r0, also change the L2 Tag RAM latency to 3 cycles */
orr x0, x0, #(L2_TAG_RAM_LATENCY_3_CYCLES << \
L2CTLR_TAG_RAM_LATENCY_SHIFT)
apply_l2_ram_latencies:
msr L2CTLR_EL1, x0
/* Juno r1 doesn't suffer from defect #831273 */
cbnz x2, ret
apply_831273:
/* --------------------------------------------------------------------
* On Juno r0, enable the event stream every 65536 cycles
* --------------------------------------------------------------------
*/
mov x0, #(0xf << EVNTI_SHIFT)
orr x0, x0, #EVNTEN_BIT
msr CNTKCTL_EL1, x0
ret:
isb
ret
endfunc plat_reset_handler