1 /* 2 * SMS/SDRC (SDRAM controller) common code for OMAP2/3 3 * 4 * Copyright (C) 2005, 2008 Texas Instruments Inc. 5 * Copyright (C) 2005, 2008 Nokia Corporation 6 * 7 * Tony Lindgren <tony@atomide.com> 8 * Paul Walmsley 9 * Richard Woodruff <r-woodruff2@ti.com> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License version 2 as 13 * published by the Free Software Foundation. 14 */ 15 #undef DEBUG 16 17 #include <linux/module.h> 18 #include <linux/kernel.h> 19 #include <linux/device.h> 20 #include <linux/list.h> 21 #include <linux/errno.h> 22 #include <linux/delay.h> 23 #include <linux/clk.h> 24 #include <linux/io.h> 25 26 #include <mach/common.h> 27 #include <mach/clock.h> 28 #include <mach/sram.h> 29 30 #include "prm.h" 31 32 #include <mach/sdrc.h> 33 #include "sdrc.h" 34 35 static struct omap_sdrc_params *sdrc_init_params; 36 37 void __iomem *omap2_sdrc_base; 38 void __iomem *omap2_sms_base; 39 40 41 /** 42 * omap2_sdrc_get_params - return SDRC register values for a given clock rate 43 * @r: SDRC clock rate (in Hz) 44 * 45 * Return pre-calculated values for the SDRC_ACTIM_CTRLA, 46 * SDRC_ACTIM_CTRLB, SDRC_RFR_CTRL, and SDRC_MR registers, for a given 47 * SDRC clock rate 'r'. These parameters control various timing 48 * delays in the SDRAM controller that are expressed in terms of the 49 * number of SDRC clock cycles to wait; hence the clock rate 50 * dependency. Note that sdrc_init_params must be sorted rate 51 * descending. Also assumes that both chip-selects use the same 52 * timing parameters. Returns a struct omap_sdrc_params * upon 53 * success, or NULL upon failure. 54 */ 55 struct omap_sdrc_params *omap2_sdrc_get_params(unsigned long r) 56 { 57 struct omap_sdrc_params *sp; 58 59 sp = sdrc_init_params; 60 61 while (sp->rate != r) 62 sp++; 63 64 if (!sp->rate) 65 return NULL; 66 67 return sp; 68 } 69 70 71 void __init omap2_set_globals_sdrc(struct omap_globals *omap2_globals) 72 { 73 omap2_sdrc_base = omap2_globals->sdrc; 74 omap2_sms_base = omap2_globals->sms; 75 } 76 77 /* turn on smart idle modes for SDRAM scheduler and controller */ 78 void __init omap2_sdrc_init(struct omap_sdrc_params *sp) 79 { 80 u32 l; 81 82 l = sms_read_reg(SMS_SYSCONFIG); 83 l &= ~(0x3 << 3); 84 l |= (0x2 << 3); 85 sms_write_reg(l, SMS_SYSCONFIG); 86 87 l = sdrc_read_reg(SDRC_SYSCONFIG); 88 l &= ~(0x3 << 3); 89 l |= (0x2 << 3); 90 sdrc_write_reg(l, SDRC_SYSCONFIG); 91 92 sdrc_init_params = sp; 93 } 94