src/arch/riscv/mcall.c

/*
 * 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 <arch/barrier.h>
#include <arch/errno.h>
#include <atomic.h>
#include <commonlib/configstring.h>
#include <console/console.h>
#include <mcall.h>
#include <string.h>
#include <vm.h>

int mcalldebug; // set this interactively for copious debug.

uintptr_t mcall_query_memory(uintptr_t id, memory_block_info *info)
{
	if (id == 0) {
		uintptr_t base;
		size_t size;

		query_mem(configstring(), &base, &size);

		mprv_write_ulong(&info->base, base);
		mprv_write_ulong(&info->size, size);
		return 0;
	}

	return -1;
}

uintptr_t mcall_send_ipi(uintptr_t recipient)
{
	die("mcall_send_ipi is currently not implemented");
	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);
		/* Ensure the other hart sees it. */
		mb();
	}

	return atomic_swap(&HLS()->ipi_pending, 0);
}

uintptr_t mcall_shutdown(void)
{
	die("mcall_shutdown is currently not implemented");
	return 0;
}

uintptr_t mcall_set_timer(uint64_t when)
{
	uint64_t *timecmp = HLS()->timecmp;

	if (mcalldebug)
		printk(BIOS_SPEW,
		       "hart %d: HLS %p: mcall timecmp@%p to 0x%llx\n",
		       HLS()->hart_id, HLS(), timecmp, when);
	*timecmp = when;
	clear_csr(mip, MIP_STIP);
	set_csr(mie, MIP_MTIP);
	return 0;
}

void hls_init(uint32_t hart_id)
{
	printk(BIOS_SPEW, "hart %d: HLS is %p\n", hart_id, HLS());
	memset(HLS(), 0, sizeof(*HLS()));
	HLS()->hart_id = hart_id;

	/* Initialize these pointers with dummy values, for now */
	HLS()->time = NULL;
	HLS()->timecmp = NULL;

	printk(BIOS_SPEW, "Time is %p and timecmp is %p\n",
	       HLS()->time, HLS()->timecmp);
}

uintptr_t mcall_console_putchar(uint8_t ch)
{
	do_putchar(ch);
	return 0;
}