pre-M1 mailbox support

Makefile

@@ -104,6 +104,7 @@ OBJECTS := \
 	adt.o \
 	afk.o \
 	aic.o \
+	akf.o \
 	asc.o \
 	bootlogo_48.o bootlogo_128.o bootlogo_256.o \
 	chainload.o \

src/akf.c

@@ -0,0 +1,131 @@
+/* SPDX-License-Identifier: MIT */
+
+#include "adt.h"
+#include "akf.h"
+#include "malloc.h"
+#include "string.h"
+#include "utils.h"
+
+// seperated from asc due to different message format
+// CPU start stop: The relvant registers do exist however it is inconsistent
+// across peripherals. Since it is unlikely that anything other than SEP
+// would be dealt with here it's best to leave start/stop registers alone.
+
+#define AKF_V1_OFF 0x1000
+#define AKF_V2_OFF 0x4000
+
+#define AKF_MBOX_CONTROL_FULL  BIT(16)
+#define AKF_MBOX_CONTROL_EMPTY BIT(17)
+
+#define AKF_MBOX_SET 0x0
+#define AKF_MBOX_CLR 0x4
+
+#define AKF_MBOX_A2I_CONTROL 0x8
+#define AKF_MBOX_A2I_SEND0   0x10
+#define AKF_MBOX_A2I_SEND1   0x14
+#define AKF_MBOX_A2I_RECV0   0x18
+#define AKF_MBOX_A2I_RECV1   0x1c
+
+#define AKF_MBOX_I2A_CONTROL 0x20
+#define AKF_MBOX_I2A_SEND0   0x30
+#define AKF_MBOX_I2A_SEND1   0x34
+#define AKF_MBOX_I2A_RECV0   0x38
+#define AKF_MBOX_I2A_RECV1   0x3c
+
+struct akf_dev {
+    uintptr_t base;
+    int iop_node;
+};
+
+akf_dev_t *akf_init(const char *path)
+{
+    int akf_path[8];
+    int node = adt_path_offset_trace(adt, path, akf_path);
+    if (node < 0) {
+        printf("akf: Error getting akf node %s\n", path);
+        return NULL;
+    }
+
+    u64 base;
+    if (adt_get_reg(adt, akf_path, "reg", 0, &base, NULL) < 0) {
+        printf("akf: Error getting akf %s base address.\n", path);
+        return NULL;
+    }
+
+    akf_dev_t *akf = calloc(1, sizeof(*akf));
+    if (!akf)
+        return NULL;
+
+    if (adt_is_compatible(adt, node, "iop,s5l8960x")) {
+        akf->base = base + AKF_V1_OFF;
+    } else if (adt_is_compatible(adt, node, "iop,s8000")) {
+        akf->base = base + AKF_V2_OFF;
+    } else {
+        printf("akf: Unsupported compatible\n");
+        goto out_free;
+    }
+
+    akf->iop_node = node;
+
+    return akf;
+
+out_free:
+    free(akf);
+    return NULL;
+}
+
+void akf_free(akf_dev_t *akf)
+{
+    free(akf);
+}
+
+int akf_get_iop_node(akf_dev_t *akf)
+{
+    return akf->iop_node;
+}
+
+bool akf_can_recv(akf_dev_t *akf)
+{
+    return !(read32(akf->base + AKF_MBOX_I2A_CONTROL) & AKF_MBOX_CONTROL_EMPTY);
+}
+
+bool akf_recv(akf_dev_t *akf, struct akf_message *msg)
+{
+    if (!akf_can_recv(akf))
+        return false;
+
+    msg->msg0 = read32(akf->base + AKF_MBOX_I2A_RECV0);
+    msg->msg1 = read32(akf->base + AKF_MBOX_I2A_RECV1);
+    dma_rmb();
+
+    return true;
+}
+
+bool akf_recv_timeout(akf_dev_t *akf, struct akf_message *msg, u32 delay_usec)
+{
+    u64 timeout = timeout_calculate(delay_usec);
+    while (!timeout_expired(timeout)) {
+        if (akf_recv(akf, msg))
+            return true;
+    }
+    return false;
+}
+
+bool akf_can_send(akf_dev_t *akf)
+{
+    return !(read32(akf->base + AKF_MBOX_A2I_CONTROL) & AKF_MBOX_CONTROL_FULL);
+}
+
+bool akf_send(akf_dev_t *akf, const struct akf_message *msg)
+{
+    if (poll32(akf->base + AKF_MBOX_A2I_CONTROL, AKF_MBOX_CONTROL_FULL, 0, 200000)) {
+        printf("akf: A2I mailbox full for 200ms. Is the akf stuck?");
+        return false;
+    }
+
+    dma_wmb();
+    write32(akf->base + AKF_MBOX_A2I_SEND0, msg->msg0);
+    write32(akf->base + AKF_MBOX_A2I_SEND1, msg->msg1);
+
+    return true;
+}

src/akf.h

@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef AKF_H
+#define AKF_H
+
+#include "types.h"
+
+struct akf_message {
+    u32 msg0;
+    u32 msg1;
+};
+
+typedef struct akf_dev akf_dev_t;
+
+akf_dev_t *akf_init(const char *path);
+void akf_free(akf_dev_t *akf);
+
+int akf_get_iop_node(akf_dev_t *akf);
+
+bool akf_can_recv(akf_dev_t *akf);
+bool akf_can_send(akf_dev_t *akf);
+
+bool akf_recv(akf_dev_t *akf, struct akf_message *msg);
+bool akf_recv_timeout(akf_dev_t *akf, struct akf_message *msg, u32 delay_usec);
+bool akf_send(akf_dev_t *akf, const struct akf_message *msg);
+
+#endif