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#define ASSEMBLY
#include <linux/config.h>
#include <config.h>
#include <asm/blackfin.h>
#include <asm/mem_init.h>
.global init_sdram;
#if (CONFIG_CCLK_DIV == 1)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV1
#endif
#if (CONFIG_CCLK_DIV == 2)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV2
#endif
#if (CONFIG_CCLK_DIV == 4)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV4
#endif
#if (CONFIG_CCLK_DIV == 8)
#define CONFIG_CCLK_ACT_DIV CCLK_DIV8
#endif
#ifndef CONFIG_CCLK_ACT_DIV
#define CONFIG_CCLK_ACT_DIV CONFIG_CCLK_DIV_not_defined_properly
#endif
init_sdram:
[--SP] = ASTAT;
[--SP] = RETS;
[--SP] = (R7:0);
[--SP] = (P5:0);
/*
* PLL_LOCKCNT - how many SCLK Cycles to delay while PLL becomes stable
*/
p0.h = hi(PLL_LOCKCNT);
p0.l = lo(PLL_LOCKCNT);
r0 = 0x300(Z);
w[p0] = r0.l;
ssync;
/*
* Put SDRAM in self-refresh, incase anything is running
*/
P2.H = hi(EBIU_SDGCTL);
P2.L = lo(EBIU_SDGCTL);
R0 = [P2];
BITSET (R0, 24);
[P2] = R0;
SSYNC;
/*
* Set PLL_CTL with the value that we calculate in R0
* - [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
*/
r0 = CONFIG_VCO_MULT & 63; /* Load the VCO multiplier */
r0 = r0 << 9; /* Shift it over, */
r1 = CONFIG_CLKIN_HALF; /* Do we need to divide CLKIN by 2? */
r0 = r1 | r0;
r1 = CONFIG_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 */
check_again:
p0.h = hi(PLL_STAT);
p0.l = lo(PLL_STAT);
R0 = W[P0](Z);
CC = BITTST(R0,5);
if ! CC jump check_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;
/*
* We now are running at speed, time to set the Async mem bank wait states
* This will speed up execution, since we are normally running from FLASH.
*/
p2.h = (EBIU_AMBCTL1 >> 16);
p2.l = (EBIU_AMBCTL1 & 0xFFFF);
r0.h = (AMBCTL1VAL >> 16);
r0.l = (AMBCTL1VAL & 0xFFFF);
[p2] = r0;
ssync;
p2.h = (EBIU_AMBCTL0 >> 16);
p2.l = (EBIU_AMBCTL0 & 0xFFFF);
r0.h = (AMBCTL0VAL >> 16);
r0.l = (AMBCTL0VAL & 0xFFFF);
[p2] = r0;
ssync;
p2.h = (EBIU_AMGCTL >> 16);
p2.l = (EBIU_AMGCTL & 0xffff);
r0 = AMGCTLVAL;
w[p2] = r0;
ssync;
/*
* Now, Initialize the SDRAM,
* start with the SDRAM Refresh Rate Control Register
*/
p0.l = lo(EBIU_SDRRC);
p0.h = hi(EBIU_SDRRC);
r0 = mem_SDRRC;
w[p0] = r0.l;
ssync;
/*
* SDRAM Memory Bank Control Register - bank specific parameters
*/
p0.l = (EBIU_SDBCTL & 0xFFFF);
p0.h = (EBIU_SDBCTL >> 16);
r0 = mem_SDBCTL;
w[p0] = r0.l;
ssync;
/*
* SDRAM Global Control Register - global programmable parameters
* Disable self-refresh
*/
P2.H = hi(EBIU_SDGCTL);
P2.L = lo(EBIU_SDGCTL);
R0 = [P2];
BITCLR (R0, 24);
/*
* Check if SDRAM is already powered up, if it is, enable self-refresh
*/
p0.h = hi(EBIU_SDSTAT);
p0.l = lo(EBIU_SDSTAT);
r2.l = w[p0];
cc = bittst(r2,3);
if !cc jump skip;
NOP;
BITSET (R0, 23);
skip:
[P2] = R0;
SSYNC;
/* Write in the new value in the register */
R0.L = lo(mem_SDGCTL);
R0.H = hi(mem_SDGCTL);
[P2] = R0;
SSYNC;
nop;
(P5:0) = [SP++];
(R7:0) = [SP++];
RETS = [SP++];
ASTAT = [SP++];
RTS;
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