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  1. /*
  2.  * Copyright (c) 2006 Ondrej Palkovsky
  3.  * Copyright (c) 2008 Martin Decky
  4.  * Copyright (c) 2008 Pavel Rimsky
  5.  * All rights reserved.
  6.  *
  7.  * Redistribution and use in source and binary forms, with or without
  8.  * modification, are permitted provided that the following conditions
  9.  * are met:
  10.  *
  11.  * - Redistributions of source code must retain the above copyright
  12.  *   notice, this list of conditions and the following disclaimer.
  13.  * - Redistributions in binary form must reproduce the above copyright
  14.  *   notice, this list of conditions and the following disclaimer in the
  15.  *   documentation and/or other materials provided with the distribution.
  16.  * - The name of the author may not be used to endorse or promote products
  17.  *   derived from this software without specific prior written permission.
  18.  *
  19.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  20.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  21.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  22.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  23.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  24.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  28.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29.  */
  30.  
  31. /** @defgroup sgcnfb SGCN
  32.  * @brief   userland driver of the Serengeti console output
  33.  * @{
  34.  */
  35. /** @file
  36.  */
  37.  
  38. #include <async.h>
  39. #include <sysinfo.h>
  40. #include <as.h>
  41. #include <errno.h>
  42. #include <stdio.h>
  43. #include <ddi.h>
  44.  
  45. #include "serial_console.h"
  46. #include "sgcn.h"
  47.  
  48. #define WIDTH 80
  49. #define HEIGHT 24
  50.  
  51. /**
  52.  * Virtual address mapped to SRAM.
  53.  */
  54. static uintptr_t sram_virt_addr;
  55.  
  56. /**
  57.  * SGCN buffer offset within SGCN.
  58.  */
  59. static uintptr_t sram_buffer_offset;
  60.  
  61. /**
  62.  * SGCN buffer header. It is placed at the very beginning of the SGCN
  63.  * buffer.
  64.  */
  65. typedef struct {
  66.     /** hard-wired to "CON" */
  67.     char magic[4];
  68.    
  69.     /** we don't need this */
  70.     char unused[24];
  71.  
  72.     /** offset within the SGCN buffer of the output buffer start */
  73.     uint32_t out_begin;
  74.    
  75.     /** offset within the SGCN buffer of the output buffer end */
  76.     uint32_t out_end;
  77.    
  78.     /** offset within the SGCN buffer of the output buffer read pointer */
  79.     uint32_t out_rdptr;
  80.    
  81.     /** offset within the SGCN buffer of the output buffer write pointer */
  82.     uint32_t out_wrptr;
  83. } __attribute__ ((packed)) sgcn_buffer_header_t;
  84.  
  85.  
  86. /*
  87.  * Returns a pointer to the object of a given type which is placed at the given
  88.  * offset from the console buffer beginning.
  89.  */
  90. #define SGCN_BUFFER(type, offset) \
  91.         ((type *) (sram_virt_addr + sram_buffer_offset + (offset)))
  92.  
  93. /** Returns a pointer to the console buffer header. */
  94. #define SGCN_BUFFER_HEADER  (SGCN_BUFFER(sgcn_buffer_header_t, 0))
  95.  
  96. /**
  97.  * Pushes the character to the SGCN serial.
  98.  * @param c character to be pushed
  99.  */
  100. static void sgcn_putc(char c)
  101. {
  102.     uint32_t begin = SGCN_BUFFER_HEADER->out_begin;
  103.     uint32_t end = SGCN_BUFFER_HEADER->out_end;
  104.     uint32_t size = end - begin;
  105.    
  106.     /* we need pointers to volatile variables */
  107.     volatile char *buf_ptr = (volatile char *)
  108.         SGCN_BUFFER(char, SGCN_BUFFER_HEADER->out_wrptr);
  109.     volatile uint32_t *out_wrptr_ptr = &(SGCN_BUFFER_HEADER->out_wrptr);
  110.     volatile uint32_t *out_rdptr_ptr = &(SGCN_BUFFER_HEADER->out_rdptr);
  111.  
  112.     uint32_t new_wrptr = (((*out_wrptr_ptr) - begin + 1) % size) + begin;
  113.     while (*out_rdptr_ptr == new_wrptr)
  114.         ;
  115.     *buf_ptr = c;
  116.     *out_wrptr_ptr = new_wrptr;
  117. }
  118.  
  119. /**
  120.  * Initializes the SGCN serial driver.
  121.  */
  122. int sgcn_init(void)
  123. {
  124.     sram_virt_addr = (uintptr_t) as_get_mappable_page(
  125.         sysinfo_value("sram.area.size"));
  126.     int result = physmem_map(
  127.         (void *) sysinfo_value("sram.address.physical"),
  128.         (void *) sram_virt_addr,
  129.         sysinfo_value("sram.area.size") / PAGE_SIZE,
  130.         AS_AREA_READ | AS_AREA_WRITE
  131.         );
  132.     if (result != 0) {
  133.         printf("SGCN: uspace driver couldn't map physical memory: %d\n",
  134.             result);
  135.     }
  136.    
  137.     serial_console_init(sgcn_putc, WIDTH, HEIGHT);
  138.    
  139.     sram_buffer_offset = sysinfo_value("sram.buffer.offset");
  140.    
  141.     async_set_client_connection(serial_client_connection);
  142.     return 0;
  143. }
  144.  
  145. /**
  146.  * @}
  147.  */
  148.  
  149.