1 //-----------------------------------------------------------------------------
2 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
3 // at your option, any later version. See the LICENSE.txt file for the text of
5 //-----------------------------------------------------------------------------
6 // Main code for the bootloader
7 //-----------------------------------------------------------------------------
12 void DbpString(char *str
) {
14 while (str
[len
] != 0x00) {
17 cmd_send_old(CMD_DEBUG_PRINT_STRING
,len
,0,0,(uint8_t*)str
,len
);
20 struct common_area common_area
__attribute__((section(".commonarea")));
21 unsigned int start_addr
, end_addr
, bootrom_unlocked
;
22 extern char _bootrom_start
, _bootrom_end
, _flash_start
, _flash_end
;
24 static void ConfigClocks(void)
26 // we are using a 16 MHz crystal as the basis for everything
27 // slow clock runs at 32Khz typical regardless of crystal
29 // enable system clock and USB clock
30 AT91C_BASE_PMC
->PMC_SCER
= AT91C_PMC_PCK
| AT91C_PMC_UDP
;
32 // enable the clock to the following peripherals
33 AT91C_BASE_PMC
->PMC_PCER
=
41 // worst case scenario, with MAINCK = 16Mhz xtal, startup delay is 1.4ms
42 // if SLCK slow clock runs at its worst case (max) frequency of 42khz
43 // max startup delay = (1.4ms*42k)/8 = 7.356 so round up to 8
45 // enable main oscillator and set startup delay
46 AT91C_BASE_PMC
->PMC_MOR
=
48 PMC_MAIN_OSC_STARTUP_DELAY(8);
50 // wait for main oscillator to stabilize
51 while ( !(AT91C_BASE_PMC
->PMC_SR
& AT91C_PMC_MOSCS
) )
54 // PLL output clock frequency in range 80 - 160 MHz needs CKGR_PLL = 00
55 // PLL output clock frequency in range 150 - 180 MHz needs CKGR_PLL = 10
56 // PLL output is MAINCK * multiplier / divisor = 16Mhz * 12 / 2 = 96Mhz
57 AT91C_BASE_PMC
->PMC_PLLR
=
59 PMC_PLL_COUNT_BEFORE_LOCK(0x50) |
60 PMC_PLL_FREQUENCY_RANGE(0) |
61 PMC_PLL_MULTIPLIER(12) |
62 PMC_PLL_USB_DIVISOR(1);
64 // wait for PLL to lock
65 while ( !(AT91C_BASE_PMC
->PMC_SR
& AT91C_PMC_LOCK
) )
68 // we want a master clock (MCK) to be PLL clock / 2 = 96Mhz / 2 = 48Mhz
69 // datasheet recommends that this register is programmed in two operations
70 // when changing to PLL, program the prescaler first then the source
71 AT91C_BASE_PMC
->PMC_MCKR
= AT91C_PMC_PRES_CLK_2
;
73 // wait for main clock ready signal
74 while ( !(AT91C_BASE_PMC
->PMC_SR
& AT91C_PMC_MCKRDY
) )
77 // set the source to PLL
78 AT91C_BASE_PMC
->PMC_MCKR
= AT91C_PMC_PRES_CLK_2
| AT91C_PMC_CSS_PLL_CLK
;
80 // wait for main clock ready signal
81 while ( !(AT91C_BASE_PMC
->PMC_SR
& AT91C_PMC_MCKRDY
) )
85 static void Fatal(void)
90 void UsbPacketReceived(UsbCommand
*c
) {
94 uint32_t arg0
= (uint32_t)c
->arg
[0];
97 case CMD_DEVICE_INFO
: {
99 arg0
= DEVICE_INFO_FLAG_BOOTROM_PRESENT
100 | DEVICE_INFO_FLAG_CURRENT_MODE_BOOTROM
101 | DEVICE_INFO_FLAG_UNDERSTANDS_START_FLASH
;
102 if(common_area
.flags
.osimage_present
) {
103 arg0
|= DEVICE_INFO_FLAG_OSIMAGE_PRESENT
;
105 cmd_send_old(CMD_DEVICE_INFO
,arg0
,1,2,0,0);
108 case CMD_SETUP_WRITE
: {
109 /* The temporary write buffer of the embedded flash controller is mapped to the
110 * whole memory region, only the last 8 bits are decoded.
112 p
= (volatile uint32_t *)&_flash_start
;
113 for(i
= 0; i
< 12; i
++) {
114 p
[i
+arg0
] = c
->d
.asDwords
[i
];
118 case CMD_FINISH_WRITE
: {
119 uint32_t* flash_mem
= (uint32_t*)(&_flash_start
);
120 for (size_t j
=0; j
<2; j
++) {
121 for(i
= 0+(64*j
); i
< 64+(64*j
); i
++) {
122 flash_mem
[i
] = c
->d
.asDwords
[i
];
125 uint32_t flash_address
= arg0
+ (0x100*j
);
127 /* Check that the address that we are supposed to write to is within our allowed region */
128 if( ((flash_address
+AT91C_IFLASH_PAGE_SIZE
-1) >= end_addr
) || (flash_address
< start_addr
) ) {
131 cmd_send_old(CMD_NACK
,0,0,0,0,0);
133 uint32_t page_n
= (flash_address
- ((uint32_t)flash_mem
)) / AT91C_IFLASH_PAGE_SIZE
;
134 /* Translate address to flash page and do flash, update here for the 512k part */
135 AT91C_BASE_EFC0
->EFC_FCR
= MC_FLASH_COMMAND_KEY
|
136 MC_FLASH_COMMAND_PAGEN(page_n
) |
137 AT91C_MC_FCMD_START_PROG
;
140 // Wait until flashing of page finishes
142 while(!((sr
= AT91C_BASE_EFC0
->EFC_FSR
) & AT91C_MC_FRDY
));
143 if(sr
& (AT91C_MC_LOCKE
| AT91C_MC_PROGE
)) {
145 cmd_send_old(CMD_NACK
,0,0,0,0,0);
150 case CMD_HARDWARE_RESET
: {
152 AT91C_BASE_RSTC
->RSTC_RCR
= RST_CONTROL_KEY
| AT91C_RSTC_PROCRST
;
155 case CMD_START_FLASH
: {
156 if(c
->arg
[2] == START_FLASH_MAGIC
) bootrom_unlocked
= 1;
157 else bootrom_unlocked
= 0;
159 int prot_start
= (int)&_bootrom_start
;
160 int prot_end
= (int)&_bootrom_end
;
161 int allow_start
= (int)&_flash_start
;
162 int allow_end
= (int)&_flash_end
;
163 int cmd_start
= c
->arg
[0];
164 int cmd_end
= c
->arg
[1];
166 /* Only allow command if the bootrom is unlocked, or the parameters are outside of the protected
167 * bootrom area. In any case they must be within the flash area.
169 if( (bootrom_unlocked
|| ((cmd_start
>= prot_end
) || (cmd_end
< prot_start
)))
170 && (cmd_start
>= allow_start
) && (cmd_end
<= allow_end
) ) {
171 start_addr
= cmd_start
;
174 start_addr
= end_addr
= 0;
176 cmd_send_old(CMD_NACK
,0,0,0,0,0);
187 cmd_send_old(CMD_ACK
,arg0
,0,0,0,0);
191 static void flash_mode(int externally_entered
)
195 bootrom_unlocked
= 0;
199 for (volatile size_t i
=0; i
<0x100000; i
++) {};
204 if (cmd_receive(&rx
)) {
205 UsbPacketReceived(&rx
);
208 if(!externally_entered
&& !BUTTON_PRESS()) {
209 /* Perform a reset to leave flash mode */
212 AT91C_BASE_RSTC
->RSTC_RCR
= RST_CONTROL_KEY
| AT91C_RSTC_PROCRST
;
215 if(externally_entered
&& BUTTON_PRESS()) {
216 /* Let the user's button press override the automatic leave */
217 externally_entered
= 0;
222 extern uint32_t _osimage_entry
;
226 // First set up all the I/O pins; GPIOs configured directly, other ones
227 // just need to be assigned to the appropriate peripheral.
229 // Kill all the pullups, especially the one on USB D+; leave them for
230 // the unused pins, though.
231 AT91C_BASE_PIOA
->PIO_PPUDR
=
249 // (and add GPIO_FPGA_ON)
250 // These pins are outputs
251 AT91C_BASE_PIOA
->PIO_OER
=
258 // PIO controls the following pins
259 AT91C_BASE_PIOA
->PIO_PER
=
266 // USB_D_PLUS_PULLUP_OFF();
273 AT91C_BASE_EFC0
->EFC_FMR
=
275 MC_FLASH_MODE_MASTER_CLK_IN_MHZ(48);
277 // Initialize all system clocks
282 int common_area_present
= 0;
283 switch(AT91C_BASE_RSTC
->RSTC_RSR
& AT91C_RSTC_RSTTYP
) {
284 case AT91C_RSTC_RSTTYP_WATCHDOG
:
285 case AT91C_RSTC_RSTTYP_SOFTWARE
:
286 case AT91C_RSTC_RSTTYP_USER
:
287 /* In these cases the common_area in RAM should be ok, retain it if it's there */
288 if(common_area
.magic
== COMMON_AREA_MAGIC
&& common_area
.version
== 1) {
289 common_area_present
= 1;
292 default: /* Otherwise, initialize it from scratch */
296 if(!common_area_present
){
297 /* Common area not ok, initialize it */
298 int i
; for(i
=0; i
<sizeof(common_area
); i
++) { /* Makeshift memset, no need to drag util.c into this */
299 ((char*)&common_area
)[i
] = 0;
301 common_area
.magic
= COMMON_AREA_MAGIC
;
302 common_area
.version
= 1;
303 common_area
.flags
.bootrom_present
= 1;
306 common_area
.flags
.bootrom_present
= 1;
307 if(common_area
.command
== COMMON_AREA_COMMAND_ENTER_FLASH_MODE
) {
308 common_area
.command
= COMMON_AREA_COMMAND_NONE
;
310 } else if(BUTTON_PRESS()) {
312 } else if(_osimage_entry
== 0xffffffffU
) {
315 // jump to Flash address of the osimage entry point (LSBit set for thumb mode)
316 __asm("bx %0\n" : : "r" ( ((int)&_osimage_entry
) | 0x1 ) );