riscv-trap-handling: Add implementation for trap calls in riscv

RISCV requires the bios/bootloader to set up an interface by which it
can get information about memory, talk to host devices, etc. Put
implementation for spike in
src/mainboard/emulation/spike-riscv/spike_util.c, and
src/arch/riscv/trap_handler.c

Change-Id: Ie1d5f361595e48fa6cc1fac25485ad623ecdc717
Signed-off-by: Thaminda Edirisooriya <thaminda@google.com>
Reviewed-on: http://review.coreboot.org/11368
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

1 files changed, 136 insertions, 0 deletions

diff --git a/src/mainboard/emulation/spike-riscv/spike_util.c b/src/mainboard/emulation/spike-riscv/spike_util.c
index b34ff4a0d0..9edc62da2b 100644
--- a/src/mainboard/emulation/spike-riscv/spike_util.c
+++ b/src/mainboard/emulation/spike-riscv/spike_util.c
@@ -1,4 +1,140 @@
+/*
+ * Copyright (c) 2013, The Regents of the University of California (Regents).
+ * All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Regents nor the
+ * names of its contributors may be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
+ * SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING
+ * OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS
+ * BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
+ * HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
+ * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ */
+
 #include <spike_util.h>
+#include <arch/errno.h>
+#include <atomic.h>
+#include <string.h>
+#include <console/console.h>
+
+uintptr_t translate_address(uintptr_t vAddr) {
+        // TODO: implement the page table translation algorithm
+        //uintptr_t pageTableRoot = read_csr(sptbr);
+        uintptr_t physAddrMask = 0xfffffff;
+        uintptr_t translationResult = vAddr & physAddrMask;
+        printk(BIOS_DEBUG, "Translated virtual address 0x%llx to physical address 0x%llx\n", vAddr, translationResult);
+        return translationResult;
+}
+
+uintptr_t mcall_query_memory(uintptr_t id, memory_block_info *p)
+{
+        uintptr_t physicalAddr = translate_address((uintptr_t) p);
+        memory_block_info *info = (memory_block_info*) physicalAddr;
+        if (id == 0) {
+                info->base = 0x1000000; // hard coded for now, but we can put these values somewhere later
+                info->size = 0x7F000000 - info->base;
+                return 0;
+        }
+
+        return -1;
+}
+
+uintptr_t mcall_send_ipi(uintptr_t recipient)
+{
+        //if (recipient >= num_harts)
+        //return -1;
+
+        if (atomic_swap(&OTHER_HLS(recipient)->ipi_pending, 1) == 0) {
+                mb();
+                write_csr(send_ipi, recipient);
+        }
+
+        return 0;
+}
+
+uintptr_t mcall_clear_ipi(void)
+{
+        // only clear SSIP if no other events are pending
+        if (HLS()->device_response_queue_head == NULL) {
+                clear_csr(mip, MIP_SSIP);
+                mb();
+        }
+
+        return atomic_swap(&HLS()->ipi_pending, 0);
+}
+
+uintptr_t mcall_shutdown(void)
+{
+        while (1) write_csr(mtohost, 1);
+        return 0;
+}
+
+uintptr_t mcall_set_timer(unsigned long long when)
+{
+        write_csr(mtimecmp, when);
+        clear_csr(mip, MIP_STIP);
+        set_csr(mie, MIP_MTIP);
+        return 0;
+}
+
+uintptr_t mcall_dev_req(sbi_device_message *m)
+{
+        if ((m->dev > 0xFFU) | (m->cmd > 0xFFU) | (m->data > 0x0000FFFFFFFFFFFFU)) return -EINVAL;
+
+        while (swap_csr(mtohost, TOHOST_CMD(m->dev, m->cmd, m->data)) != 0);
+
+        m->sbi_private_data = (uintptr_t)HLS()->device_request_queue_head;
+        HLS()->device_request_queue_head = m;
+        HLS()->device_request_queue_size++;
+
+        return 0;
+}
+
+uintptr_t mcall_dev_resp(void)
+{
+        htif_interrupt(0, 0);
+
+        sbi_device_message* m = HLS()->device_response_queue_head;
+        if (m) {
+                //printm("resp %p\n", m);
+                sbi_device_message* next = (void*)atomic_read(&m->sbi_private_data);
+                HLS()->device_response_queue_head = next;
+                if (!next) {
+                        HLS()->device_response_queue_tail = 0;
+
+                        // only clear SSIP if no other events are pending
+                        clear_csr(mip, MIP_SSIP);
+                        mb();
+                        if (HLS()->ipi_pending) set_csr(mip, MIP_SSIP);
+                }
+        }
+        return (uintptr_t)m;
+}
+
+uintptr_t mcall_hart_id(void)
+{
+        return HLS()->hart_id;
+}
+
+void hls_init(uint32_t hart_id)
+{
+        memset(HLS(), 0, sizeof(*HLS()));
+        HLS()->hart_id = hart_id;
+}
 
 uintptr_t htif_interrupt(uintptr_t mcause, uintptr_t* regs) {
         uintptr_t fromhost = swap_csr(mfromhost, 0);