2 * File: arch/blackfin/mach-bf537/head.S
3 * Based on: arch/blackfin/mach-bf533/head.S
4 * Author: Jeff Dionne <jeff@uclinux.org> COPYRIGHT 1998 D. Jeff Dionne
7 * Description: Startup code for Blackfin BF537
10 * Copyright 2004-2006 Analog Devices Inc.
12 * Bugs: Enter bugs at http://blackfin.uclinux.org/
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, see the file COPYING, or write
26 * to the Free Software Foundation, Inc.,
27 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
30 #include <linux/linkage.h>
31 #include <linux/init.h>
32 #include <asm/blackfin.h>
33 #include <asm/trace.h>
35 #if CONFIG_BFIN_KERNEL_CLOCK
36 #include <asm/mach-common/clocks.h>
37 #include <asm/mach/mem_init.h>
45 .extern _bf53x_relocate_l1_mem
47 #define INITIAL_STACK 0xFFB01000
52 /* R0: argument of command line string, passed from uboot, save it */
54 /* Enable Cycle Counter and Nesting Of Interrupts */
55 #ifdef CONFIG_BFIN_SCRATCH_REG_CYCLES
58 R0 = SYSCFG_SNEN | SYSCFG_CCEN;
63 /* Clear Out All the data and pointer Registers */
85 /* Clear Out All the DAG Registers */
101 trace_buffer_init(p0,r0);
105 /* Turn off the icache */
106 p0.l = LO(IMEM_CONTROL);
107 p0.h = HI(IMEM_CONTROL);
112 /* Anomaly 05000125 */
123 /* Turn off the dcache */
124 p0.l = LO(DMEM_CONTROL);
125 p0.h = HI(DMEM_CONTROL);
130 /* Anomaly 05000125 */
141 /* Initialise General-Purpose I/O Modules on BF537 */
142 /* Rev 0.0 Anomaly 05000212 - PORTx_FER,
143 * PORT_MUX Registers Do Not accept "writes" correctly:
145 p0.h = hi(BFIN_PORT_MUX);
146 p0.l = lo(BFIN_PORT_MUX);
148 R0.L = W[P0]; /* Read */
151 R0 = (PGDE_UART | PFTE_UART)(Z);
153 W[P0] = R0.L; /* Write */
156 W[P0] = R0.L; /* Enable both UARTS */
159 p0.h = hi(PORTF_FER);
160 p0.l = lo(PORTF_FER);
162 R0.L = W[P0]; /* Read */
167 W[P0] = R0.L; /* Write */
170 /* Enable peripheral function of PORTF for UART0 and UART1 */
174 #if !defined(CONFIG_BF534)
175 p0.h = hi(EMAC_SYSTAT);
176 p0.l = lo(EMAC_SYSTAT);
177 R0.h = 0xFFFF; /* Clear EMAC Interrupt Status bits */
183 /* Initialise UART - when booting from u-boot, the UART is not disabled
184 * so if we dont initalize here, our serial console gets hosed */
185 p0.h = hi(BFIN_UART_LCR);
186 p0.l = lo(BFIN_UART_LCR);
188 w[p0] = r0.L; /* To enable DLL writes */
191 p0.h = hi(BFIN_UART_DLL);
192 p0.l = lo(BFIN_UART_DLL);
197 p0.h = hi(BFIN_UART_DLH);
198 p0.l = lo(BFIN_UART_DLH);
203 p0.h = hi(BFIN_UART_GCTL);
204 p0.l = lo(BFIN_UART_GCTL);
206 w[p0] = r0.L; /* To enable UART clock */
209 /* Initialize stack pointer */
210 sp.l = lo(INITIAL_STACK);
211 sp.h = hi(INITIAL_STACK);
215 #ifdef CONFIG_EARLY_PRINTK
217 call _init_early_exception_vectors;
221 /* Put The Code for PLL Programming and SDRAM Programming in L1 ISRAM */
222 call _bf53x_relocate_l1_mem;
223 #if CONFIG_BFIN_KERNEL_CLOCK
224 call _start_dma_code;
227 /* Code for initializing Async memory banks */
229 p2.h = hi(EBIU_AMBCTL1);
230 p2.l = lo(EBIU_AMBCTL1);
231 r0.h = hi(AMBCTL1VAL);
232 r0.l = lo(AMBCTL1VAL);
236 p2.h = hi(EBIU_AMBCTL0);
237 p2.l = lo(EBIU_AMBCTL0);
238 r0.h = hi(AMBCTL0VAL);
239 r0.l = lo(AMBCTL0VAL);
243 p2.h = hi(EBIU_AMGCTL);
244 p2.l = lo(EBIU_AMGCTL);
249 /* This section keeps the processor in supervisor mode
250 * during kernel boot. Switches to user mode at end of boot.
251 * See page 3-9 of Hardware Reference manual for documentation.
254 /* EVT15 = _real_start */
288 w[p0] = r0; /* watchdog off for now */
291 /* Code update for BSS size == 0
292 * Zero out the bss region.
301 lsetup (.L_clear_bss, .L_clear_bss) lc0 = p2;
305 /* In case there is a NULL pointer reference
306 * Zero out region before stext
316 lsetup (.L_clear_zero, .L_clear_zero) lc0 = p2;
320 /* pass the uboot arguments to the global value command line */
339 * load the current thread pointer and stack
341 r1.l = _init_thread_union;
342 r1.h = _init_thread_union;
350 jump.l _start_kernel;
356 #if CONFIG_BFIN_KERNEL_CLOCK
357 ENTRY(_start_dma_code)
359 /* Enable PHY CLK buffer output */
376 * - [14:09] = MSEL[5:0] : CLKIN / VCO multiplication factors
377 * - [8] = BYPASS : BYPASS the PLL, run CLKIN into CCLK/SCLK
378 * - [7] = output delay (add 200ps of delay to mem signals)
379 * - [6] = input delay (add 200ps of input delay to mem signals)
380 * - [5] = PDWN : 1=All Clocks off
381 * - [3] = STOPCK : 1=Core Clock off
382 * - [1] = PLL_OFF : 1=Disable Power to PLL
383 * - [0] = DF : 1=Pass CLKIN/2 to PLL / 0=Pass CLKIN to PLL
384 * all other bits set to zero
387 p0.h = hi(PLL_LOCKCNT);
388 p0.l = lo(PLL_LOCKCNT);
393 P2.H = hi(EBIU_SDGCTL);
394 P2.L = lo(EBIU_SDGCTL);
400 r0 = CONFIG_VCO_MULT & 63; /* Load the VCO multiplier */
401 r0 = r0 << 9; /* Shift it over, */
402 r1 = CLKIN_HALF; /* Do we need to divide CLKIN by 2?*/
404 r1 = PLL_BYPASS; /* Bypass the PLL? */
405 r1 = r1 << 8; /* Shift it over */
406 r0 = r1 | r0; /* add them all together */
409 p0.l = lo(PLL_CTL); /* Load the address */
410 cli r2; /* Disable interrupts */
412 w[p0] = r0.l; /* Set the value */
413 idle; /* Wait for the PLL to stablize */
414 sti r2; /* Enable interrupts */
421 if ! CC jump .Lcheck_again;
423 /* Configure SCLK & CCLK Dividers */
424 r0 = (CONFIG_CCLK_ACT_DIV | CONFIG_SCLK_DIV);
430 p0.l = lo(EBIU_SDRRC);
431 p0.h = hi(EBIU_SDRRC);
436 p0.l = LO(EBIU_SDBCTL);
437 p0.h = HI(EBIU_SDBCTL); /* SDRAM Memory Bank Control Register */
442 P2.H = hi(EBIU_SDGCTL);
443 P2.L = lo(EBIU_SDGCTL);
446 p0.h = hi(EBIU_SDSTAT);
447 p0.l = lo(EBIU_SDSTAT);
457 R0.L = lo(mem_SDGCTL);
458 R0.H = hi(mem_SDGCTL);
466 r0.l = lo(IWR_ENABLE_ALL);
467 r0.h = hi(IWR_ENABLE_ALL);
472 ENDPROC(_start_dma_code)
473 #endif /* CONFIG_BFIN_KERNEL_CLOCK */
478 * Set up the usable of RAM stuff. Size of RAM is determined then
479 * an initial stack set up at the end.