zephyr/soc/mediatek/mtk_adsp/mbox.c

131 lines
3.7 KiB
C

/* Copyright 2023 The ChromiumOS Authors
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/device.h>
#include <zephyr/irq.h>
#include <zephyr/devicetree.h>
#include <soc.h>
#define DT_DRV_COMPAT mediatek_mbox
/* Mailbox: a simple interrupt source. Each direction has a 5-bit
* command register and will latch an interrupt if any of the bits are
* non-zero. The interrupt bits get cleared/acknowledged by writing
* ones to the corresponding bits of "cmd_clear". There are five
* scratch registers for use as message data in each direction.
*
* The same device is mapped at the same address by the host and DSP,
* and the naming is from the perspective of the DSP: the "in"
* registers control interrupts on the DSP, the "out" registers are
* for transmitting data to the host.
*
* There is an array of the devices. Linux's device-tree defines two.
* SOF uses those for IPC, but also implements platform_trace_point()
* using the third (no linux driver though?). The upstream headers
* list interrupts for FIVE, and indeed those all seem to be present
* and working.
*
* In practice: The first device (mbox0) is for IPC commands in both
* directions. The cmd register is written with a 1 ("IPI_OP_REQ")
* and the command is placed in shared DRAM. The message registers
* are ignored. The second device (mbox1) is for responses to IPC
* commands, writing a 2 (IPI_OP_RSP) to the command register. (Yes,
* this is redundant, and the actual value is ignored by the ISRs on
* both sides).
*/
struct mtk_mbox {
uint32_t in_cmd;
uint32_t in_cmd_clr;
uint32_t in_msg[5];
uint32_t out_cmd;
uint32_t out_cmd_clr;
uint32_t out_msg[5];
};
struct mbox_cfg {
volatile struct mtk_mbox *mbox;
uint32_t irq;
};
struct mbox_data {
mtk_adsp_mbox_handler_t handlers[MTK_ADSP_MBOX_CHANNELS];
void *handler_arg[MTK_ADSP_MBOX_CHANNELS];
};
void mtk_adsp_mbox_set_handler(const struct device *mbox, uint32_t chan,
mtk_adsp_mbox_handler_t handler, void *arg)
{
struct mbox_data *data = ((struct device *)mbox)->data;
if (chan < MTK_ADSP_MBOX_CHANNELS) {
data->handlers[chan] = handler;
data->handler_arg[chan] = arg;
}
}
void mtk_adsp_mbox_set_msg(const struct device *mbox, uint32_t idx, uint32_t val)
{
const struct mbox_cfg *cfg = ((struct device *)mbox)->config;
if (idx < MTK_ADSP_MBOX_MSG_WORDS) {
cfg->mbox->out_msg[idx] = val;
}
}
uint32_t mtk_adsp_mbox_get_msg(const struct device *mbox, uint32_t idx)
{
const struct mbox_cfg *cfg = ((struct device *)mbox)->config;
if (idx < MTK_ADSP_MBOX_MSG_WORDS) {
return cfg->mbox->in_msg[idx];
}
return 0;
}
void mtk_adsp_mbox_signal(const struct device *mbox, uint32_t chan)
{
const struct mbox_cfg *cfg = ((struct device *)mbox)->config;
if (chan < MTK_ADSP_MBOX_CHANNELS) {
cfg->mbox->out_cmd |= BIT(chan);
}
}
static void mbox_isr(const void *arg)
{
const struct mbox_cfg *cfg = ((struct device *)arg)->config;
struct mbox_data *data = ((struct device *)arg)->data;
for (int i = 0; i < MTK_ADSP_MBOX_CHANNELS; i++) {
if (cfg->mbox->in_cmd & BIT(i)) {
if (data->handlers[i] != NULL) {
data->handlers[i](arg, data->handler_arg[i]);
}
}
}
cfg->mbox->in_cmd_clr = cfg->mbox->in_cmd; /* ACK */
}
#define DEF_IRQ(N) \
IRQ_CONNECT(DT_INST_IRQN(N), 0, mbox_isr, DEVICE_DT_INST_GET(N), 0);
static int mbox_init(void)
{
DT_INST_FOREACH_STATUS_OKAY(DEF_IRQ);
return 0;
}
SYS_INIT(mbox_init, POST_KERNEL, 0);
#define DEF_DEV(N) \
static struct mbox_data dev_data##N; \
static const struct mbox_cfg dev_cfg##N = \
{ .irq = DT_INST_IRQN(N), .mbox = (void *)DT_INST_REG_ADDR(N), }; \
DEVICE_DT_INST_DEFINE(N, NULL, NULL, &dev_data##N, &dev_cfg##N, \
POST_KERNEL, 0, NULL);
DT_INST_FOREACH_STATUS_OKAY(DEF_DEV)