RISC-V HTIF Console

HTIF (Host Target Interface) provides console emulation for QEMU. HTIF
allows identical copies of BBL (Berkeley Boot Loader) and linux to run
on both Spike and QEMU. BBL provides HTIF console access via the
SBI (Supervisor Binary Interface) and the linux kernel SBI console.

The HTIT chardev implements the pre qom legacy interface consistent
with the 16550a UART in 'hw/char/serial.c'.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu>
Signed-off-by: Stefan O'Rear <sorear2@gmail.com>
Signed-off-by: Michael Clark <mjc@sifive.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/include/hw/riscv/riscv_htif.h b/include/hw/riscv/riscv_htif.h
new file mode 100644
index 0000000000..fb5f88129e
--- /dev/null
+++ b/include/hw/riscv/riscv_htif.h
@@ -0,0 +1,61 @@
+/*
+ * QEMU RISCV Host Target Interface (HTIF) Emulation
+ *
+ * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
+ * Copyright (c) 2017-2018 SiFive, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef HW_RISCV_HTIF_H
+#define HW_RISCV_HTIF_H
+
+#include "hw/hw.h"
+#include "chardev/char.h"
+#include "chardev/char-fe.h"
+#include "sysemu/sysemu.h"
+#include "exec/memory.h"
+#include "target/riscv/cpu.h"
+
+#define TYPE_HTIF_UART "riscv.htif.uart"
+
+typedef struct HTIFState {
+    int allow_tohost;
+    int fromhost_inprogress;
+
+    hwaddr tohost_offset;
+    hwaddr fromhost_offset;
+    uint64_t tohost_size;
+    uint64_t fromhost_size;
+    MemoryRegion mmio;
+    MemoryRegion *address_space;
+    MemoryRegion *main_mem;
+    void *main_mem_ram_ptr;
+
+    CPURISCVState *env;
+    CharBackend chr;
+    uint64_t pending_read;
+} HTIFState;
+
+extern const VMStateDescription vmstate_htif;
+extern const MemoryRegionOps htif_io_ops;
+
+/* HTIF symbol callback */
+void htif_symbol_callback(const char *st_name, int st_info, uint64_t st_value,
+    uint64_t st_size);
+
+/* legacy pre qom */
+HTIFState *htif_mm_init(MemoryRegion *address_space, MemoryRegion *main_mem,
+    CPURISCVState *env, Chardev *chr);
+
+#endif