1 /***********************license start***************
2 * Copyright (c) 2003-2010 Cavium Inc. ([email protected]). All rights
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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-clock.h>
45 #include <asm/octeon/cvmx-uart.h>
46 #else
47 #include "cvmx.h"
48 #include "cvmx-uart.h"
49 #include "cvmx-interrupt.h"
50 #endif
51
52 #ifndef CVMX_BUILD_FOR_TOOLCHAIN
cvmx_uart_enable_intr(int uart,cvmx_uart_intr_handler_t handler)53 void cvmx_uart_enable_intr(int uart, cvmx_uart_intr_handler_t handler)
54 {
55 #ifndef CVMX_BUILD_FOR_LINUX_KERNEL
56 cvmx_uart_ier_t ier;
57
58 cvmx_interrupt_register(CVMX_IRQ_UART0 + uart, handler, NULL);
59 /* Enable uart interrupts for debugger Control-C processing */
60 ier.u64 = cvmx_read_csr(CVMX_MIO_UARTX_IER(uart));
61 ier.s.erbfi = 1;
62 cvmx_write_csr(CVMX_MIO_UARTX_IER(uart), ier.u64);
63
64 cvmx_interrupt_unmask_irq(CVMX_IRQ_UART0 + uart);
65 #endif
66 }
67 #endif
68
cvmx_uart_simulator_p(void)69 static int cvmx_uart_simulator_p(void)
70 {
71 #ifndef CVMX_BUILD_FOR_TOOLCHAIN
72 return cvmx_sysinfo_get()->board_type == CVMX_BOARD_TYPE_SIM;
73 #else
74 extern int __octeon_simulator_p;
75 return __octeon_simulator_p;
76 #endif
77 }
78
79
80 /**
81 * Function that does the real work of setting up the Octeon uart.
82 * Takes all parameters as arguments, so it does not require gd
83 * structure to be set up.
84 *
85 * @param uart_index Index of uart to configure
86 * @param cpu_clock_hertz
87 * CPU clock frequency in Hz
88 * @param baudrate Baudrate to configure
89 *
90 * @return 0 on success
91 * !0 on error
92 */
cvmx_uart_setup2(int uart_index,int cpu_clock_hertz,int baudrate)93 int cvmx_uart_setup2(int uart_index, int cpu_clock_hertz, int baudrate)
94 {
95 uint16_t divisor;
96 cvmx_uart_fcr_t fcrval;
97 cvmx_uart_mcr_t mcrval;
98 cvmx_uart_lcr_t lcrval;
99
100 fcrval.u64 = 0;
101 fcrval.s.en = 1; /* enable the FIFO's */
102 fcrval.s.rxfr = 1; /* reset the RX fifo */
103 fcrval.s.txfr = 1; /* reset the TX fifo */
104
105 if (cvmx_uart_simulator_p())
106 divisor = 1;
107 else
108 divisor = ((unsigned long)(cpu_clock_hertz + 8 * baudrate) / (unsigned long)(16 * baudrate));
109
110 cvmx_write_csr(CVMX_MIO_UARTX_FCR(uart_index), fcrval.u64);
111
112 mcrval.u64 = 0;
113 if (uart_index == 1 && cvmx_uart_simulator_p())
114 mcrval.s.afce = 1; /* enable auto flow control for simulator. Needed for gdb regression callfuncs.exp. */
115 else
116 mcrval.s.afce = 0; /* disable auto flow control so board can power on without serial port connected */
117
118 mcrval.s.rts = 1; /* looks like this must be set for auto flow control to work */
119
120 cvmx_read_csr(CVMX_MIO_UARTX_LSR(uart_index));
121
122 lcrval.u64 = 0;
123 lcrval.s.cls = CVMX_UART_BITS8;
124 lcrval.s.stop = 0; /* stop bit included? */
125 lcrval.s.pen = 0; /* no parity? */
126 lcrval.s.eps = 1; /* even parity? */
127 lcrval.s.dlab = 1; /* temporary to program the divisor */
128 cvmx_write_csr(CVMX_MIO_UARTX_LCR(uart_index), lcrval.u64);
129
130 cvmx_write_csr(CVMX_MIO_UARTX_DLL(uart_index), divisor & 0xff);
131 cvmx_write_csr(CVMX_MIO_UARTX_DLH(uart_index), (divisor>>8) & 0xff);
132
133 lcrval.s.dlab = 0; /* divisor is programmed now, set this back to normal */
134 cvmx_write_csr(CVMX_MIO_UARTX_LCR(uart_index), lcrval.u64);
135
136 /* spec says need to wait after you program the divisor */
137 if (!cvmx_uart_simulator_p())
138 {
139 uint64_t read_cycle;
140 CVMX_MF_CYCLE (read_cycle);
141 read_cycle += (2 * divisor * 16) + 10000;
142
143 /* Spin */
144 while (1)
145 {
146 uint64_t new_cycle;
147 CVMX_MF_CYCLE (new_cycle);
148 if (new_cycle >= read_cycle)
149 break;
150 }
151 }
152
153 /* Don't enable flow control until after baud rate is configured. - we don't want
154 ** to allow characters in until after the baud rate is fully configured */
155 cvmx_write_csr(CVMX_MIO_UARTX_MCR(uart_index), mcrval.u64);
156 return 0;
157
158 }
159
160 /**
161 * Setup a uart for use
162 *
163 * @param uart_index Uart to setup (0 or 1)
164 * @return Zero on success
165 */
cvmx_uart_setup(int uart_index)166 int cvmx_uart_setup (int uart_index)
167 {
168 return cvmx_uart_setup2(uart_index, cvmx_clock_get_rate (CVMX_CLOCK_SCLK), 115200);
169 }
170
171