blob: 56f44e0f2afc2ae563100460cecf90a24f781010 [file] [log] [blame]
/*
* Copyright (c) 2019-2020, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <assert.h>
#include <arch_helpers.h>
#include <drivers/delay_timer.h>
#include <lib/bakery_lock.h>
#include <brcm_mhu.h>
#include <platform_def.h>
#include "m0_ipc.h"
#define PLAT_MHU_INTR_REG AP_TO_SCP_MAILBOX1
/* SCP MHU secure channel registers */
#define SCP_INTR_S_STAT CRMU_IHOST_SW_PERSISTENT_REG11
#define SCP_INTR_S_SET CRMU_IHOST_SW_PERSISTENT_REG11
#define SCP_INTR_S_CLEAR CRMU_IHOST_SW_PERSISTENT_REG11
/* CPU MHU secure channel registers */
#define CPU_INTR_S_STAT CRMU_IHOST_SW_PERSISTENT_REG10
#define CPU_INTR_S_SET CRMU_IHOST_SW_PERSISTENT_REG10
#define CPU_INTR_S_CLEAR CRMU_IHOST_SW_PERSISTENT_REG10
static DEFINE_BAKERY_LOCK(bcm_lock);
/*
* Slot 31 is reserved because the MHU hardware uses this register bit to
* indicate a non-secure access attempt. The total number of available slots is
* therefore 31 [30:0].
*/
#define MHU_MAX_SLOT_ID 30
void mhu_secure_message_start(unsigned int slot_id)
{
int iter = 1000000;
assert(slot_id <= MHU_MAX_SLOT_ID);
bakery_lock_get(&bcm_lock);
/* Make sure any previous command has finished */
do {
if (!(mmio_read_32(PLAT_BRCM_MHU_BASE + CPU_INTR_S_STAT) &
(1 << slot_id)))
break;
udelay(1);
} while (--iter);
assert(iter != 0);
}
void mhu_secure_message_send(unsigned int slot_id)
{
uint32_t response, iter = 1000000;
assert(slot_id <= MHU_MAX_SLOT_ID);
assert(!(mmio_read_32(PLAT_BRCM_MHU_BASE + CPU_INTR_S_STAT) &
(1 << slot_id)));
/* Send command to SCP */
mmio_setbits_32(PLAT_BRCM_MHU_BASE + CPU_INTR_S_SET, 1 << slot_id);
mmio_write_32(CRMU_MAIL_BOX0, MCU_IPC_MCU_CMD_SCPI);
mmio_write_32(PLAT_BRCM_MHU_BASE + PLAT_MHU_INTR_REG, 0x1);
/* Wait until IPC transport acknowledges reception of SCP command */
do {
response = mmio_read_32(CRMU_MAIL_BOX0);
if ((response & ~MCU_IPC_CMD_REPLY_MASK) ==
(MCU_IPC_CMD_DONE_MASK | MCU_IPC_MCU_CMD_SCPI))
break;
udelay(1);
} while (--iter);
assert(iter != 0);
}
uint32_t mhu_secure_message_wait(void)
{
/* Wait for response from SCP */
uint32_t response, iter = 1000000;
do {
response = mmio_read_32(PLAT_BRCM_MHU_BASE + SCP_INTR_S_STAT);
if (!response)
break;
udelay(1);
} while (--iter);
assert(iter != 0);
return response;
}
void mhu_secure_message_end(unsigned int slot_id)
{
assert(slot_id <= MHU_MAX_SLOT_ID);
/*
* Clear any response we got by writing one in the relevant slot bit to
* the CLEAR register
*/
mmio_clrbits_32(PLAT_BRCM_MHU_BASE + SCP_INTR_S_CLEAR, 1 << slot_id);
bakery_lock_release(&bcm_lock);
}
void mhu_secure_init(void)
{
bakery_lock_init(&bcm_lock);
/*
* The STAT register resets to zero. Ensure it is in the expected state,
* as a stale or garbage value would make us think it's a message we've
* already sent.
*/
mmio_write_32(PLAT_BRCM_MHU_BASE + CPU_INTR_S_STAT, 0);
mmio_write_32(PLAT_BRCM_MHU_BASE + SCP_INTR_S_STAT, 0);
}
void plat_brcm_pwrc_setup(void)
{
mhu_secure_init();
}