1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (c) 2016 IBM Corporation.
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #include "ops.h"
7*4882a593Smuzhiyun #include "stdio.h"
8*4882a593Smuzhiyun #include "io.h"
9*4882a593Smuzhiyun #include <libfdt.h>
10*4882a593Smuzhiyun #include "../include/asm/opal-api.h"
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun /* Global OPAL struct used by opal-call.S */
13*4882a593Smuzhiyun struct opal {
14*4882a593Smuzhiyun u64 base;
15*4882a593Smuzhiyun u64 entry;
16*4882a593Smuzhiyun } opal;
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun static u32 opal_con_id;
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun /* see opal-wrappers.S */
21*4882a593Smuzhiyun int64_t opal_console_write(int64_t term_number, u64 *length, const u8 *buffer);
22*4882a593Smuzhiyun int64_t opal_console_read(int64_t term_number, uint64_t *length, u8 *buffer);
23*4882a593Smuzhiyun int64_t opal_console_write_buffer_space(uint64_t term_number, uint64_t *length);
24*4882a593Smuzhiyun int64_t opal_console_flush(uint64_t term_number);
25*4882a593Smuzhiyun int64_t opal_poll_events(uint64_t *outstanding_event_mask);
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun void opal_kentry(unsigned long fdt_addr, void *vmlinux_addr);
28*4882a593Smuzhiyun
opal_con_open(void)29*4882a593Smuzhiyun static int opal_con_open(void)
30*4882a593Smuzhiyun {
31*4882a593Smuzhiyun /*
32*4882a593Smuzhiyun * When OPAL loads the boot kernel it stashes the OPAL base and entry
33*4882a593Smuzhiyun * address in r8 and r9 so the kernel can use the OPAL console
34*4882a593Smuzhiyun * before unflattening the devicetree. While executing the wrapper will
35*4882a593Smuzhiyun * probably trash r8 and r9 so this kentry hook restores them before
36*4882a593Smuzhiyun * entering the decompressed kernel.
37*4882a593Smuzhiyun */
38*4882a593Smuzhiyun platform_ops.kentry = opal_kentry;
39*4882a593Smuzhiyun return 0;
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
opal_con_putc(unsigned char c)42*4882a593Smuzhiyun static void opal_con_putc(unsigned char c)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun int64_t rc;
45*4882a593Smuzhiyun uint64_t olen, len;
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun do {
48*4882a593Smuzhiyun rc = opal_console_write_buffer_space(opal_con_id, &olen);
49*4882a593Smuzhiyun len = be64_to_cpu(olen);
50*4882a593Smuzhiyun if (rc)
51*4882a593Smuzhiyun return;
52*4882a593Smuzhiyun opal_poll_events(NULL);
53*4882a593Smuzhiyun } while (len < 1);
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun olen = cpu_to_be64(1);
57*4882a593Smuzhiyun opal_console_write(opal_con_id, &olen, &c);
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun
opal_con_close(void)60*4882a593Smuzhiyun static void opal_con_close(void)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun opal_console_flush(opal_con_id);
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun
opal_init(void)65*4882a593Smuzhiyun static void opal_init(void)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun void *opal_node;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun opal_node = finddevice("/ibm,opal");
70*4882a593Smuzhiyun if (!opal_node)
71*4882a593Smuzhiyun return;
72*4882a593Smuzhiyun if (getprop(opal_node, "opal-base-address", &opal.base, sizeof(u64)) < 0)
73*4882a593Smuzhiyun return;
74*4882a593Smuzhiyun opal.base = be64_to_cpu(opal.base);
75*4882a593Smuzhiyun if (getprop(opal_node, "opal-entry-address", &opal.entry, sizeof(u64)) < 0)
76*4882a593Smuzhiyun return;
77*4882a593Smuzhiyun opal.entry = be64_to_cpu(opal.entry);
78*4882a593Smuzhiyun }
79*4882a593Smuzhiyun
opal_console_init(void * devp,struct serial_console_data * scdp)80*4882a593Smuzhiyun int opal_console_init(void *devp, struct serial_console_data *scdp)
81*4882a593Smuzhiyun {
82*4882a593Smuzhiyun opal_init();
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun if (devp) {
85*4882a593Smuzhiyun int n = getprop(devp, "reg", &opal_con_id, sizeof(u32));
86*4882a593Smuzhiyun if (n != sizeof(u32))
87*4882a593Smuzhiyun return -1;
88*4882a593Smuzhiyun opal_con_id = be32_to_cpu(opal_con_id);
89*4882a593Smuzhiyun } else
90*4882a593Smuzhiyun opal_con_id = 0;
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun scdp->open = opal_con_open;
93*4882a593Smuzhiyun scdp->putc = opal_con_putc;
94*4882a593Smuzhiyun scdp->close = opal_con_close;
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun return 0;
97*4882a593Smuzhiyun }
98