blob: cc4a6ffcbe480b3a2c929618558d42b5a222581f [file] [log] [blame]
/*
* Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <assert.h>
#include <stdbool.h>
#include <drivers/delay_timer.h>
#include <lib/bakery_lock.h>
#include <lib/mmio.h>
#include <lib/utils_def.h>
#include <sunxi_mmap.h>
#define REMOTE_IRQ_EN_REG 0x0040
#define REMOTE_IRQ_STAT_REG 0x0050
#define LOCAL_IRQ_EN_REG 0x0060
#define LOCAL_IRQ_STAT_REG 0x0070
#define RX_IRQ(n) BIT(0 + 2 * (n))
#define TX_IRQ(n) BIT(1 + 2 * (n))
#define FIFO_STAT_REG(n) (0x0100 + 0x4 * (n))
#define FIFO_STAT_MASK GENMASK(0, 0)
#define MSG_STAT_REG(n) (0x0140 + 0x4 * (n))
#define MSG_STAT_MASK GENMASK(2, 0)
#define MSG_DATA_REG(n) (0x0180 + 0x4 * (n))
#define RX_CHAN 1
#define TX_CHAN 0
#define MHU_MAX_SLOT_ID 31
#define MHU_TIMEOUT_DELAY 10
#define MHU_TIMEOUT_ITERS 10000
static DEFINE_BAKERY_LOCK(mhu_secure_message_lock);
static bool sunxi_msgbox_last_tx_done(unsigned int chan)
{
uint32_t stat = mmio_read_32(SUNXI_MSGBOX_BASE + REMOTE_IRQ_STAT_REG);
return (stat & RX_IRQ(chan)) == 0U;
}
static bool sunxi_msgbox_peek_data(unsigned int chan)
{
uint32_t stat = mmio_read_32(SUNXI_MSGBOX_BASE + MSG_STAT_REG(chan));
return (stat & MSG_STAT_MASK) != 0U;
}
void mhu_secure_message_start(unsigned int slot_id __unused)
{
uint32_t timeout = MHU_TIMEOUT_ITERS;
bakery_lock_get(&mhu_secure_message_lock);
/* Wait for all previous messages to be acknowledged. */
while (!sunxi_msgbox_last_tx_done(TX_CHAN) && --timeout)
udelay(MHU_TIMEOUT_DELAY);
}
void mhu_secure_message_send(unsigned int slot_id)
{
mmio_write_32(SUNXI_MSGBOX_BASE + MSG_DATA_REG(TX_CHAN), BIT(slot_id));
}
uint32_t mhu_secure_message_wait(void)
{
uint32_t timeout = MHU_TIMEOUT_ITERS;
uint32_t msg = 0;
/* Wait for a message from the SCP. */
while (!sunxi_msgbox_peek_data(RX_CHAN) && --timeout)
udelay(MHU_TIMEOUT_DELAY);
/* Return the most recent message in the FIFO. */
while (sunxi_msgbox_peek_data(RX_CHAN))
msg = mmio_read_32(SUNXI_MSGBOX_BASE + MSG_DATA_REG(RX_CHAN));
return msg;
}
void mhu_secure_message_end(unsigned int slot_id)
{
/* Acknowledge a response by clearing the IRQ status. */
mmio_write_32(SUNXI_MSGBOX_BASE + LOCAL_IRQ_STAT_REG, RX_IRQ(RX_CHAN));
bakery_lock_release(&mhu_secure_message_lock);
}