1 /*
2 * Copyright (c) 2015 Google Inc. All rights reserved
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files
6 * (the "Software"), to deal in the Software without restriction,
7 * including without limitation the rights to use, copy, modify, merge,
8 * publish, distribute, sublicense, and/or sell copies of the Software,
9 * and to permit persons to whom the Software is furnished to do so,
10 * subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22 */
23
24 #include <kernel/thread.h>
25 #include <kernel/vm.h>
26 #include <lib/device_tree/libfdt_helpers.h>
27 #include <lk/reg.h>
28 #include <lk/types.h>
29 #include <platform/debug.h>
30 #if MMIO_GUARD_ENABLED
31 #include <err.h>
32 #include <lib/libhypervisor/libhypervisor.h>
33 #endif
34
35 #include "debug.h"
36
37 #if GENERIC_ARM64_DEBUG_SMC_DEBUG_PUTC
38 #include "smc.h"
39 #endif
40
41 #if GENERIC_ARM64_DEBUG_FFA
42 #include <lib/arm_ffa/arm_ffa.h>
43 #endif
44
45 #if GENERIC_ARM64_DEBUG_UART
46 enum uart_type {
47 UART_NONE,
48 UART_PL011,
49 UART_8250,
50 };
51
52 static uint8_t* uart_base;
53 static enum uart_type uart_type;
54
map_uart(paddr_t reg_paddr,enum uart_type new_uart_type)55 static void map_uart(paddr_t reg_paddr, enum uart_type new_uart_type) {
56 int ret;
57 void* page_vaddr;
58
59 ASSERT(!uart_base);
60
61 paddr_t reg_pbase = round_down(reg_paddr, PAGE_SIZE);
62 ret = vmm_alloc_physical(
63 vmm_get_kernel_aspace(), "uart", PAGE_SIZE, &page_vaddr, 0,
64 reg_pbase, 0,
65 ARCH_MMU_FLAG_PERM_NO_EXECUTE | ARCH_MMU_FLAG_UNCACHED_DEVICE);
66 if (ret) {
67 return;
68 }
69
70 #if MMIO_GUARD_ENABLED
71 /*
72 * MMIO Guard map UART registers. Ignore not supported which implies that
73 * guard is not used.
74 *
75 * TODO: Figure out why we sometimes get ERR_INVALID_ARGS when MMIO Guard is
76 * not supported. It happens on qemu-generic-arm64-gicv3-test-debug builds.
77 */
78 ret = hypervisor_mmio_map_region(reg_pbase, PAGE_SIZE);
79 if (ret != NO_ERROR && ret != ERR_NOT_SUPPORTED &&
80 ret != ERR_INVALID_ARGS) {
81 dprintf(CRITICAL, "failed to mmio guard map uart. error=%d\n", ret);
82 return;
83 }
84 #endif
85
86 uart_type = new_uart_type;
87 uart_base = (uint8_t*)page_vaddr + (reg_paddr - reg_pbase);
88 }
89
generic_arm64_setup_uart(const void * fdt)90 void generic_arm64_setup_uart(const void* fdt) {
91 enum uart_type uart_type;
92 int fdt_chosen_offset = fdt_path_offset(fdt, "/chosen");
93 int fdt_stdout_path_len;
94 const char* fdt_stdout_path = fdt_getprop(
95 fdt, fdt_chosen_offset, "stdout-path", &fdt_stdout_path_len);
96 if (!fdt_stdout_path) {
97 return;
98 }
99 int fdt_stdout_offset = fdt_path_offset_namelen(fdt, fdt_stdout_path,
100 fdt_stdout_path_len - 1);
101
102 if (!fdt_node_check_compatible(fdt, fdt_stdout_offset, "arm,pl011")) {
103 uart_type = UART_PL011;
104 } else if (!fdt_node_check_compatible(fdt, fdt_stdout_offset, "ns8250") ||
105 !fdt_node_check_compatible(fdt, fdt_stdout_offset, "ns16550a")) {
106 uart_type = UART_8250;
107 } else {
108 return;
109 }
110
111 paddr_t uart_reg;
112 if (fdt_helper_get_reg(fdt, fdt_stdout_offset, 0, &uart_reg, NULL)) {
113 return;
114 }
115
116 map_uart(uart_reg, uart_type);
117 }
118 #endif
119
platform_dputc(char c)120 void platform_dputc(char c) {
121 #if GENERIC_ARM64_DEBUG_SMC_DEBUG_PUTC
122 generic_arm64_smc(SMC_FC_DEBUG_PUTC, (unsigned long)c, 0, 0);
123 #elif GENERIC_ARM64_DEBUG_FFA
124 arm_ffa_console_log(&c, 1);
125 #elif GENERIC_ARM64_DEBUG_UART
126 if (!uart_base) {
127 return;
128 }
129 if (uart_type == UART_8250) {
130 while (!(readb(uart_base + 5) & (1U << 5))) {
131 }
132 writeb(c, uart_base + 0);
133 } else if (uart_type == UART_PL011) {
134 while ((*REG16(uart_base + 0x018) & (1U << 5))) {
135 }
136 *REG16(uart_base + 0x000) = c;
137 }
138 #else
139 #error Unsupported GENERIC_ARM64_DEBUG mode
140 #endif
141 }
142
platform_dgetc(char * c,bool wait)143 int platform_dgetc(char* c, bool wait) {
144 int ret = -1;
145
146 while (wait)
147 thread_sleep(100);
148
149 return ret;
150 }
151