arch/v850/kernel/as85ep1.c

   1 /*
   2  * arch/v850/kernel/as85ep1.c -- AS85EP1 V850E evaluation chip/board
   3  *
   4  *  Copyright (C) 2002,03  NEC Electronics Corporation
   5  *  Copyright (C) 2002,03  Miles Bader <miles@gnu.org>
   6  *
   7  * This file is subject to the terms and conditions of the GNU General
   8  * Public License.  See the file COPYING in the main directory of this
   9  * archive for more details.
  10  *
  11  * Written by Miles Bader <miles@gnu.org>
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/bootmem.h>
  18 #include <linux/major.h>
  19 #include <linux/irq.h>
  20
  21 #include <asm/machdep.h>
  22 #include <asm/atomic.h>
  23 #include <asm/page.h>
  24 #include <asm/v850e_timer_d.h>
  25 #include <asm/v850e_uart.h>
  26
  27 #include "mach.h"
  28
  29
  30 /* SRAM and SDRAM are vaguely contiguous (with a big hole in between; see
  31    mach_reserve_bootmem for details); use both as one big area.  */
  32 #define RAM_START       SRAM_ADDR
  33 #define RAM_END         (SDRAM_ADDR + SDRAM_SIZE)
  34
  35 /* The bits of this port are connected to an 8-LED bar-graph.  */
  36 #define LEDS_PORT       4
  37
  38
  39 static void as85ep1_led_tick (void);
  40
  41 extern char _intv_copy_src_start, _intv_copy_src_end;
  42 extern char _intv_copy_dst_start;
  43
  44
  45 void __init mach_early_init (void)
  46 {
  47 #ifndef CONFIG_ROM_KERNEL
  48         const u32 *src;
  49         register u32 *dst asm ("ep");
  50 #endif
  51
  52         AS85EP1_CSC(0) = 0x0403;
  53         AS85EP1_BCT(0) = 0xB8B8;
  54         AS85EP1_DWC(0) = 0x0104;
  55         AS85EP1_BCC    = 0x0012;
  56         AS85EP1_ASC    = 0;
  57         AS85EP1_LBS    = 0x00A9;
  58
  59         AS85EP1_PORT_PMC(6)  = 0xFF; /* valid A0,A1,A20-A25 */
  60         AS85EP1_PORT_PMC(7)  = 0x0E; /* valid CS1-CS3       */
  61         AS85EP1_PORT_PMC(9)  = 0xFF; /* valid D16-D23       */
  62         AS85EP1_PORT_PMC(10) = 0xFF; /* valid D24-D31       */
  63
  64         AS85EP1_RFS(1) = 0x800c;
  65         AS85EP1_RFS(3) = 0x800c;
  66         AS85EP1_SCR(1) = 0x20A9;
  67         AS85EP1_SCR(3) = 0x20A9;
  68
  69 #ifndef CONFIG_ROM_KERNEL
  70         /* The early chip we have is buggy, and writing the interrupt
  71            vectors into low RAM may screw up, so for non-ROM kernels, we
  72            only rely on the reset vector being downloaded, and copy the
  73            rest of the interrupt vectors into place here.  The specific bug
  74            is that writing address N, where (N & 0x10) == 0x10, will _also_
  75            write to address (N - 0x10).  We avoid this (effectively) by
  76            writing in 16-byte chunks backwards from the end.  */
  77
  78         AS85EP1_IRAMM = 0x3;    /* "write-mode" for the internal instruction memory */
  79
  80         src = (u32 *)(((u32)&_intv_copy_src_end - 1) & ~0xF);
  81         dst = (u32 *)&_intv_copy_dst_start
  82                 + (src - (u32 *)&_intv_copy_src_start);
  83         do {
  84                 u32 t0 = src[0], t1 = src[1], t2 = src[2], t3 = src[3];
  85                 dst[0] = t0; dst[1] = t1; dst[2] = t2; dst[3] = t3;
  86                 dst -= 4;
  87                 src -= 4;
  88         } while (src > (u32 *)&_intv_copy_src_start);
  89
  90         AS85EP1_IRAMM = 0x0;    /* "read-mode" for the internal instruction memory */
  91 #endif /* !CONFIG_ROM_KERNEL */
  92
  93         v850e_intc_disable_irqs ();
  94 }
  95
  96 void __init mach_setup (char **cmdline)
  97 {
  98         AS85EP1_PORT_PMC (LEDS_PORT) = 0; /* Make the LEDs port an I/O port. */
  99         AS85EP1_PORT_PM (LEDS_PORT) = 0; /* Make all the bits output pins.  */
 100         mach_tick = as85ep1_led_tick;
 101 }
 102
 103 void __init mach_get_physical_ram (unsigned long *ram_start,
 104                                    unsigned long *ram_len)
 105 {
 106         *ram_start = RAM_START;
 107         *ram_len = RAM_END - RAM_START;
 108 }
 109
 110 /* Convenience macros.  */
 111 #define SRAM_END        (SRAM_ADDR + SRAM_SIZE)
 112 #define SDRAM_END       (SDRAM_ADDR + SDRAM_SIZE)
 113
 114 void __init mach_reserve_bootmem ()
 115 {
 116         if (SDRAM_ADDR < RAM_END && SDRAM_ADDR > RAM_START)
 117                 /* We can't use the space between SRAM and SDRAM, so
 118                    prevent the kernel from trying.  */
 119                 reserve_bootmem(SRAM_END, SDRAM_ADDR - SRAM_END,
 120                                 BOOTMEM_DEFAULT);
 121 }
 122
 123 void mach_gettimeofday (struct timespec *tv)
 124 {
 125         tv->tv_sec = 0;
 126         tv->tv_nsec = 0;
 127 }
 128
 129 void __init mach_sched_init (struct irqaction *timer_action)
 130 {
 131         /* Start hardware timer.  */
 132         v850e_timer_d_configure (0, HZ);
 133         /* Install timer interrupt handler.  */
 134         setup_irq (IRQ_INTCMD(0), timer_action);
 135 }
 136
 137 static struct v850e_intc_irq_init irq_inits[] = {
 138         { "IRQ", 0,             NUM_MACH_IRQS,  1, 7 },
 139         { "CCC", IRQ_INTCCC(0), IRQ_INTCCC_NUM, 1, 5 },
 140         { "CMD", IRQ_INTCMD(0), IRQ_INTCMD_NUM, 1, 5 },
 141         { "SRE", IRQ_INTSRE(0), IRQ_INTSRE_NUM, 3, 3 },
 142         { "SR",  IRQ_INTSR(0),  IRQ_INTSR_NUM,  3, 4 },
 143         { "ST",  IRQ_INTST(0),  IRQ_INTST_NUM,  3, 5 },
 144         { 0 }
 145 };
 146 #define NUM_IRQ_INITS (ARRAY_SIZE(irq_inits) - 1)
 147
 148 static struct hw_interrupt_type hw_itypes[NUM_IRQ_INITS];
 149
 150 void __init mach_init_irqs (void)
 151 {
 152         v850e_intc_init_irq_types (irq_inits, hw_itypes);
 153 }
 154
 155 void machine_restart (char *__unused)
 156 {
 157 #ifdef CONFIG_RESET_GUARD
 158         disable_reset_guard ();
 159 #endif
 160         asm ("jmp r0"); /* Jump to the reset vector.  */
 161 }
 162
 163 void machine_halt (void)
 164 {
 165 #ifdef CONFIG_RESET_GUARD
 166         disable_reset_guard ();
 167 #endif
 168         local_irq_disable ();   /* Ignore all interrupts.  */
 169         AS85EP1_PORT_IO (LEDS_PORT) = 0xAA;     /* Note that we halted.  */
 170         for (;;)
 171                 asm ("halt; nop; nop; nop; nop; nop");
 172 }
 173
 174 void machine_power_off (void)
 175 {
 176         machine_halt ();
 177 }
 178
 179 /* Called before configuring an on-chip UART.  */
 180 void as85ep1_uart_pre_configure (unsigned chan, unsigned cflags, unsigned baud)
 181 {
 182         /* Make the shared uart/port pins be uart pins.  */
 183         AS85EP1_PORT_PMC(3) |= (0x5 << chan);
 184
 185         /* The AS85EP1 connects some general-purpose I/O pins on the CPU to
 186            the RTS/CTS lines of UART 1's serial connection.  I/O pins P53
 187            and P54 are RTS and CTS respectively.  */
 188         if (chan == 1) {
 189                 /* Put P53 & P54 in I/O port mode.  */
 190                 AS85EP1_PORT_PMC(5) &= ~0x18;
 191                 /* Make P53 an output, and P54 an input.  */
 192                 AS85EP1_PORT_PM(5) |=  0x10;
 193         }
 194 }
 195
 196 /* Minimum and maximum bounds for the moving upper LED boundary in the
 197    clock tick display.  */
 198 #define MIN_MAX_POS 0
 199 #define MAX_MAX_POS 7
 200
 201 /* There are MAX_MAX_POS^2 - MIN_MAX_POS^2 cycles in the animation, so if
 202    we pick 6 and 0 as above, we get 49 cycles, which is when divided into
 203    the standard 100 value for HZ, gives us an almost 1s total time.  */
 204 #define TICKS_PER_FRAME \
 205         (HZ / (MAX_MAX_POS * MAX_MAX_POS - MIN_MAX_POS * MIN_MAX_POS))
 206
 207 static void as85ep1_led_tick ()
 208 {
 209         static unsigned counter = 0;
 210
 211         if (++counter == TICKS_PER_FRAME) {
 212                 static int pos = 0, max_pos = MAX_MAX_POS, dir = 1;
 213
 214                 if (dir > 0 && pos == max_pos) {
 215                         dir = -1;
 216                         if (max_pos == MIN_MAX_POS)
 217                                 max_pos = MAX_MAX_POS;
 218                         else
 219                                 max_pos--;
 220                 } else {
 221                         if (dir < 0 && pos == 0)
 222                                 dir = 1;
 223
 224                         if (pos + dir <= max_pos) {
 225                                 /* Each bit of port 0 has a LED. */
 226                                 set_bit (pos, &AS85EP1_PORT_IO(LEDS_PORT));
 227                                 pos += dir;
 228                                 clear_bit (pos, &AS85EP1_PORT_IO(LEDS_PORT));
 229                         }
 230                 }
 231
 232                 counter = 0;
 233         }
 234 }