/* * File: arch/blackfin/mach-bf533/head.S * Based on: * Author: Jeff Dionne COPYRIGHT 1998 D. Jeff Dionne * * Created: 1998 * Description: bf533 startup file * * Modified: * Copyright 2004-2006 Analog Devices Inc. * * Bugs: Enter bugs at http://blackfin.uclinux.org/ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see the file COPYING, or write * to the Free Software Foundation, Inc., * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include #include #include #ifdef CONFIG_BFIN_KERNEL_CLOCK #include #include #endif .extern ___bss_stop .extern ___bss_start .extern _bf53x_relocate_l1_mem #define INITIAL_STACK 0xFFB01000 __INIT ENTRY(__start) /* R0: argument of command line string, passed from uboot, save it */ R7 = R0; /* Enable Cycle Counter and Nesting Of Interrupts */ #ifdef CONFIG_BFIN_SCRATCH_REG_CYCLES R0 = SYSCFG_SNEN; #else R0 = SYSCFG_SNEN | SYSCFG_CCEN; #endif SYSCFG = R0; R0 = 0; /* Clear Out All the data and pointer Registers */ R1 = R0; R2 = R0; R3 = R0; R4 = R0; R5 = R0; R6 = R0; P0 = R0; P1 = R0; P2 = R0; P3 = R0; P4 = R0; P5 = R0; LC0 = r0; LC1 = r0; L0 = r0; L1 = r0; L2 = r0; L3 = r0; /* Clear Out All the DAG Registers */ B0 = r0; B1 = r0; B2 = r0; B3 = r0; I0 = r0; I1 = r0; I2 = r0; I3 = r0; M0 = r0; M1 = r0; M2 = r0; M3 = r0; trace_buffer_init(p0,r0); P0 = R1; R0 = R1; p0.h = hi(FIO_MASKA_C); p0.l = lo(FIO_MASKA_C); r0 = 0xFFFF(Z); w[p0] = r0.L; /* Disable all interrupts */ ssync; p0.h = hi(FIO_MASKB_C); p0.l = lo(FIO_MASKB_C); r0 = 0xFFFF(Z); w[p0] = r0.L; /* Disable all interrupts */ ssync; /* Turn off the icache */ p0.l = LO(IMEM_CONTROL); p0.h = HI(IMEM_CONTROL); R1 = [p0]; R0 = ~ENICPLB; R0 = R0 & R1; [p0] = R0; SSYNC; /* Turn off the dcache */ p0.l = LO(DMEM_CONTROL); p0.h = HI(DMEM_CONTROL); R1 = [p0]; R0 = ~ENDCPLB; R0 = R0 & R1; [p0] = R0; SSYNC; /* Initialise UART - when booting from u-boot, the UART is not disabled * so if we dont initalize here, our serial console gets hosed */ p0.h = hi(BFIN_UART_LCR); p0.l = lo(BFIN_UART_LCR); r0 = 0x0(Z); w[p0] = r0.L; /* To enable DLL writes */ ssync; p0.h = hi(BFIN_UART_DLL); p0.l = lo(BFIN_UART_DLL); r0 = 0x0(Z); w[p0] = r0.L; ssync; p0.h = hi(BFIN_UART_DLH); p0.l = lo(BFIN_UART_DLH); r0 = 0x00(Z); w[p0] = r0.L; ssync; p0.h = hi(BFIN_UART_GCTL); p0.l = lo(BFIN_UART_GCTL); r0 = 0x0(Z); w[p0] = r0.L; /* To enable UART clock */ ssync; /* Initialize stack pointer */ sp.l = lo(INITIAL_STACK); sp.h = hi(INITIAL_STACK); fp = sp; usp = sp; #ifdef CONFIG_EARLY_PRINTK SP += -12; call _init_early_exception_vectors; SP += 12; #endif /* Put The Code for PLL Programming and SDRAM Programming in L1 ISRAM */ call _bf53x_relocate_l1_mem; #ifdef CONFIG_BFIN_KERNEL_CLOCK call _start_dma_code; #endif /* Code for initializing Async memory banks */ p2.h = hi(EBIU_AMBCTL1); p2.l = lo(EBIU_AMBCTL1); r0.h = hi(AMBCTL1VAL); r0.l = lo(AMBCTL1VAL); [p2] = r0; ssync; p2.h = hi(EBIU_AMBCTL0); p2.l = lo(EBIU_AMBCTL0); r0.h = hi(AMBCTL0VAL); r0.l = lo(AMBCTL0VAL); [p2] = r0; ssync; p2.h = hi(EBIU_AMGCTL); p2.l = lo(EBIU_AMGCTL); r0 = AMGCTLVAL; w[p2] = r0; ssync; /* This section keeps the processor in supervisor mode * during kernel boot. Switches to user mode at end of boot. * See page 3-9 of Hardware Reference manual for documentation. */ /* EVT15 = _real_start */ p0.l = lo(EVT15); p0.h = hi(EVT15); p1.l = _real_start; p1.h = _real_start; [p0] = p1; csync; p0.l = lo(IMASK); p0.h = hi(IMASK); p1.l = IMASK_IVG15; p1.h = 0x0; [p0] = p1; csync; raise 15; p0.l = .LWAIT_HERE; p0.h = .LWAIT_HERE; reti = p0; #if ANOMALY_05000281 nop; nop; nop; #endif rti; .LWAIT_HERE: jump .LWAIT_HERE; ENDPROC(__start) ENTRY(_real_start) [ -- sp ] = reti; p0.l = lo(WDOG_CTL); p0.h = hi(WDOG_CTL); r0 = 0xAD6(z); w[p0] = r0; /* watchdog off for now */ ssync; /* Code update for BSS size == 0 * Zero out the bss region. */ p1.l = ___bss_start; p1.h = ___bss_start; p2.l = ___bss_stop; p2.h = ___bss_stop; r0 = 0; p2 -= p1; lsetup (.L_clear_bss, .L_clear_bss) lc0 = p2; .L_clear_bss: B[p1++] = r0; /* In case there is a NULL pointer reference * Zero out region before stext */ p1.l = 0x0; p1.h = 0x0; r0.l = __stext; r0.h = __stext; r0 = r0 >> 1; p2 = r0; r0 = 0; lsetup (.L_clear_zero, .L_clear_zero) lc0 = p2; .L_clear_zero: W[p1++] = r0; /* pass the uboot arguments to the global value command line */ R0 = R7; call _cmdline_init; p1.l = __rambase; p1.h = __rambase; r0.l = __sdata; r0.h = __sdata; [p1] = r0; p1.l = __ramstart; p1.h = __ramstart; p3.l = ___bss_stop; p3.h = ___bss_stop; r1 = p3; [p1] = r1; /* * load the current thread pointer and stack */ r1.l = _init_thread_union; r1.h = _init_thread_union; r2.l = 0x2000; r2.h = 0x0000; r1 = r1 + r2; sp = r1; usp = sp; fp = sp; jump.l _start_kernel; ENDPROC(_real_start) __FINIT .section .l1.text #ifdef CONFIG_BFIN_KERNEL_CLOCK ENTRY(_start_dma_code) p0.h = hi(SIC_IWR); p0.l = lo(SIC_IWR); r0.l = 0x1; r0.h = 0x0; [p0] = r0; SSYNC; /* * Set PLL_CTL * - [14:09] = MSEL[5:0] : CLKIN / VCO multiplication factors * - [8] = BYPASS : BYPASS the PLL, run CLKIN into CCLK/SCLK * - [7] = output delay (add 200ps of delay to mem signals) * - [6] = input delay (add 200ps of input delay to mem signals) * - [5] = PDWN : 1=All Clocks off * - [3] = STOPCK : 1=Core Clock off * - [1] = PLL_OFF : 1=Disable Power to PLL * - [0] = DF : 1=Pass CLKIN/2 to PLL / 0=Pass CLKIN to PLL * all other bits set to zero */ p0.h = hi(PLL_LOCKCNT); p0.l = lo(PLL_LOCKCNT); r0 = 0x300(Z); w[p0] = r0.l; ssync; P2.H = hi(EBIU_SDGCTL); P2.L = lo(EBIU_SDGCTL); R0 = [P2]; BITSET (R0, 24); [P2] = R0; SSYNC; r0 = CONFIG_VCO_MULT & 63; /* Load the VCO multiplier */ r0 = r0 << 9; /* Shift it over, */ r1 = CLKIN_HALF; /* Do we need to divide CLKIN by 2?*/ r0 = r1 | r0; r1 = PLL_BYPASS; /* Bypass the PLL? */ r1 = r1 << 8; /* Shift it over */ r0 = r1 | r0; /* add them all together */ p0.h = hi(PLL_CTL); p0.l = lo(PLL_CTL); /* Load the address */ cli r2; /* Disable interrupts */ ssync; w[p0] = r0.l; /* Set the value */ idle; /* Wait for the PLL to stablize */ sti r2; /* Enable interrupts */ .Lcheck_again: p0.h = hi(PLL_STAT); p0.l = lo(PLL_STAT); R0 = W[P0](Z); CC = BITTST(R0,5); if ! CC jump .Lcheck_again; /* Configure SCLK & CCLK Dividers */ r0 = (CONFIG_CCLK_ACT_DIV | CONFIG_SCLK_DIV); p0.h = hi(PLL_DIV); p0.l = lo(PLL_DIV); w[p0] = r0.l; ssync; p0.l = lo(EBIU_SDRRC); p0.h = hi(EBIU_SDRRC); r0 = mem_SDRRC; w[p0] = r0.l; ssync; P2.H = hi(EBIU_SDGCTL); P2.L = lo(EBIU_SDGCTL); R0 = [P2]; BITCLR (R0, 24); p0.h = hi(EBIU_SDSTAT); p0.l = lo(EBIU_SDSTAT); r2.l = w[p0]; cc = bittst(r2,3); if !cc jump .Lskip; NOP; BITSET (R0, 23); .Lskip: [P2] = R0; SSYNC; R0.L = lo(mem_SDGCTL); R0.H = hi(mem_SDGCTL); R1 = [p2]; R1 = R1 | R0; [P2] = R1; SSYNC; p0.h = hi(SIC_IWR); p0.l = lo(SIC_IWR); r0.l = lo(IWR_ENABLE_ALL); r0.h = hi(IWR_ENABLE_ALL); [p0] = r0; SSYNC; RTS; ENDPROC(_start_dma_code) #endif /* CONFIG_BFIN_KERNEL_CLOCK */