1/***********************license start***************
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23 * This Software, including technical data, may be subject to U.S. export  control
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37 * PERFORMANCE OF THE SOFTWARE LIES WITH YOU.
38 ***********************license end**************************************/
39
40
41#ifdef CVMX_BUILD_FOR_LINUX_KERNEL
42#include <linux/module.h>
43#include <asm/octeon/cvmx.h>
44#include <asm/octeon/cvmx-debug.h>
45#include <asm/octeon/cvmx-uart.h>
46#include <asm/octeon/octeon-boot-info.h>
47#include <asm/octeon/cvmx-spinlock.h>
48
49int cvmx_debug_uart = 1;
50
51#else
52#include <limits.h>
53#include "executive-config.h"
54#include "cvmx.h"
55#include "cvmx-debug.h"
56#include "cvmx-uart.h"
57#include "cvmx-spinlock.h"
58#include "octeon-boot-info.h"
59#endif
60
61/*
62 * NOTE: CARE SHOULD BE TAKEN USING STD C LIBRARY FUNCTIONS IN
63 * THIS FILE IF SOMEONE PUTS A BREAKPOINT ON THOSE FUNCTIONS
64 * DEBUGGING WILL FAIL.
65 */
66
67
68#ifdef CVMX_BUILD_FOR_TOOLCHAIN
69#pragma weak cvmx_uart_enable_intr
70int cvmx_debug_uart = 1;
71#endif
72
73
74/* Default to second uart port for backward compatibility.  The default (if
75   -debug does not set the uart number) can now be overridden with
76   CVMX_DEBUG_COMM_UART_NUM. */
77#ifndef CVMX_DEBUG_COMM_UART_NUM
78# define CVMX_DEBUG_COMM_UART_NUM 1
79#endif
80
81static CVMX_SHARED cvmx_spinlock_t cvmx_debug_uart_lock;
82
83/**
84 * Interrupt handler for debugger Control-C interrupts.
85 *
86 * @param irq_number IRQ interrupt number
87 * @param registers  CPU registers at the time of the interrupt
88 * @param user_arg   Unused user argument
89 */
90void cvmx_debug_uart_process_debug_interrupt(int irq_number, uint64_t registers[32], void *user_arg)
91{
92    cvmx_uart_lsr_t lsrval;
93
94    /* Check for a Control-C interrupt from the debugger. This loop will eat
95        all input received on the uart */
96    lsrval.u64 = cvmx_read_csr(CVMX_MIO_UARTX_LSR(cvmx_debug_uart));
97    while (lsrval.s.dr)
98    {
99        int c = cvmx_read_csr(CVMX_MIO_UARTX_RBR(cvmx_debug_uart));
100        if (c == '\003')
101        {
102            register uint64_t tmp;
103#ifndef CVMX_BUILD_FOR_LINUX_KERNEL
104            fflush(stderr);
105            fflush(stdout);
106#endif
107            /* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also
108                set the MCD0 to be not masked by this core so we know
109                the signal is received by someone */
110            asm volatile (
111                "dmfc0 %0, $22\n"
112                "ori   %0, %0, 0x1110\n"
113                "dmtc0 %0, $22\n"
114                : "=r" (tmp));
115        }
116        lsrval.u64 = cvmx_read_csr(CVMX_MIO_UARTX_LSR(cvmx_debug_uart));
117    }
118}
119
120
121static void cvmx_debug_uart_init(void)
122{
123    if (cvmx_debug_uart == -1)
124	cvmx_debug_uart = CVMX_DEBUG_COMM_UART_NUM;
125}
126
127static void cvmx_debug_uart_install_break_handler(void)
128{
129#ifndef CVMX_BUILD_FOR_LINUX_KERNEL
130#ifdef CVMX_BUILD_FOR_TOOLCHAIN
131    if (cvmx_uart_enable_intr)
132#endif
133        cvmx_uart_enable_intr(cvmx_debug_uart, cvmx_debug_uart_process_debug_interrupt);
134#endif
135}
136
137/**
138 * Routines to handle hex data
139 *
140 * @param ch
141 * @return
142 */
143static inline int cvmx_debug_uart_hex(char ch)
144{
145    if ((ch >= 'a') && (ch <= 'f'))
146        return(ch - 'a' + 10);
147    if ((ch >= '0') && (ch <= '9'))
148        return(ch - '0');
149    if ((ch >= 'A') && (ch <= 'F'))
150        return(ch - 'A' + 10);
151    return(-1);
152}
153
154/* Get a packet from the UART, return 0 on failure and 1 on success. */
155
156static int cvmx_debug_uart_getpacket(char *buffer, size_t size)
157{
158    while (1)
159    {
160	unsigned char checksum;
161        int timedout = 0;
162	size_t count;
163	char ch;
164
165        ch = cvmx_uart_read_byte_with_timeout(cvmx_debug_uart, &timedout, __SHRT_MAX__);
166
167        if (timedout)
168            return 0;
169
170        /* if this is not the start character, ignore it. */
171        if (ch != '$')
172            continue;
173
174        retry:
175        checksum = 0;
176        count = 0;
177
178        /* now, read until a # or end of buffer is found */
179        while (count < size)
180        {
181            ch = cvmx_uart_read_byte(cvmx_debug_uart);
182            if (ch == '$')
183                goto retry;
184            if (ch == '#')
185                break;
186            checksum = checksum + ch;
187            buffer[count] = ch;
188            count = count + 1;
189        }
190        buffer[count] = 0;
191
192        if (ch == '#')
193        {
194	    char csumchars0, csumchars1;
195	    unsigned xmitcsum;
196	    int n0, n1;
197
198            csumchars0 = cvmx_uart_read_byte(cvmx_debug_uart);
199            csumchars1 = cvmx_uart_read_byte(cvmx_debug_uart);
200            n0 = cvmx_debug_uart_hex(csumchars0);
201            n1 = cvmx_debug_uart_hex(csumchars1);
202	    if (n0 == -1 || n1 == -1)
203		return 0;
204
205            xmitcsum = (n0 << 4) | n1;
206            return checksum == xmitcsum;
207        }
208    }
209    return 0;
210}
211
212/* Put the hex value of t into str. */
213static void cvmx_debug_uart_strhex(char *str, unsigned char t)
214{
215  char hexchar[] = "0123456789ABCDEF";
216  str[0] = hexchar[(t>>4)];
217  str[1] = hexchar[t&0xF];
218  str[2] = 0;
219}
220
221static int cvmx_debug_uart_putpacket(char *packet)
222{
223    size_t i;
224    unsigned char csum;
225    unsigned char *ptr = (unsigned char *) packet;
226    char csumstr[3];
227
228    for (csum = 0, i = 0; ptr[i]; i++)
229      csum += ptr[i];
230    cvmx_debug_uart_strhex(csumstr, csum);
231
232    cvmx_spinlock_lock(&cvmx_debug_uart_lock);
233    cvmx_uart_write_byte(cvmx_debug_uart, '$');
234    cvmx_uart_write_string(cvmx_debug_uart, packet);
235    cvmx_uart_write_byte(cvmx_debug_uart, '#');
236    cvmx_uart_write_string(cvmx_debug_uart, csumstr);
237    cvmx_spinlock_unlock(&cvmx_debug_uart_lock);
238
239    return 0;
240}
241
242static void cvmx_debug_uart_change_core(int oldcore, int newcore)
243{
244#ifndef CVMX_BUILD_FOR_LINUX_KERNEL
245    cvmx_ciu_intx0_t irq_control;
246
247    irq_control.u64 = cvmx_read_csr(CVMX_CIU_INTX_EN0(newcore * 2));
248    irq_control.s.uart |= (1u<<cvmx_debug_uart);
249    cvmx_write_csr(CVMX_CIU_INTX_EN0(newcore * 2), irq_control.u64);
250
251    /* Disable interrupts to this core since he is about to die */
252    irq_control.u64 = cvmx_read_csr(CVMX_CIU_INTX_EN0(oldcore * 2));
253    irq_control.s.uart &= ~(1u<<cvmx_debug_uart);
254    cvmx_write_csr(CVMX_CIU_INTX_EN0(oldcore* 2), irq_control.u64);
255#endif
256}
257
258cvmx_debug_comm_t cvmx_debug_uart_comm =
259{
260  .init = cvmx_debug_uart_init,
261  .install_break_handler = cvmx_debug_uart_install_break_handler,
262  .needs_proxy = 1,
263  .getpacket = cvmx_debug_uart_getpacket,
264  .putpacket = cvmx_debug_uart_putpacket,
265  .wait_for_resume = NULL,
266  .change_core = cvmx_debug_uart_change_core,
267};
268