diff options
Diffstat (limited to 'arch/arm/mach-omap2/sdrc.c')
-rw-r--r-- | arch/arm/mach-omap2/sdrc.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/sdrc.c b/arch/arm/mach-omap2/sdrc.c new file mode 100644 index 00000000000..2a30060cb4b --- /dev/null +++ b/arch/arm/mach-omap2/sdrc.c @@ -0,0 +1,93 @@ +/* + * SMS/SDRC (SDRAM controller) common code for OMAP2/3 + * + * Copyright (C) 2005, 2008 Texas Instruments Inc. + * Copyright (C) 2005, 2008 Nokia Corporation + * + * Tony Lindgren <tony@atomide.com> + * Paul Walmsley + * Richard Woodruff <r-woodruff2@ti.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#undef DEBUG + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/list.h> +#include <linux/errno.h> +#include <linux/delay.h> +#include <linux/clk.h> +#include <linux/io.h> + +#include <mach/common.h> +#include <mach/clock.h> +#include <mach/sram.h> + +#include "prm.h" + +#include <mach/sdrc.h> +#include "sdrc.h" + +static struct omap_sdrc_params *sdrc_init_params; + +void __iomem *omap2_sdrc_base; +void __iomem *omap2_sms_base; + + +/** + * omap2_sdrc_get_params - return SDRC register values for a given clock rate + * @r: SDRC clock rate (in Hz) + * + * Return pre-calculated values for the SDRC_ACTIM_CTRLA, + * SDRC_ACTIM_CTRLB, SDRC_RFR_CTRL, and SDRC_MR registers, for a given + * SDRC clock rate 'r'. These parameters control various timing + * delays in the SDRAM controller that are expressed in terms of the + * number of SDRC clock cycles to wait; hence the clock rate + * dependency. Note that sdrc_init_params must be sorted rate + * descending. Also assumes that both chip-selects use the same + * timing parameters. Returns a struct omap_sdrc_params * upon + * success, or NULL upon failure. + */ +struct omap_sdrc_params *omap2_sdrc_get_params(unsigned long r) +{ + struct omap_sdrc_params *sp; + + sp = sdrc_init_params; + + while (sp->rate != r) + sp++; + + if (!sp->rate) + return NULL; + + return sp; +} + + +void __init omap2_set_globals_sdrc(struct omap_globals *omap2_globals) +{ + omap2_sdrc_base = omap2_globals->sdrc; + omap2_sms_base = omap2_globals->sms; +} + +/* turn on smart idle modes for SDRAM scheduler and controller */ +void __init omap2_sdrc_init(struct omap_sdrc_params *sp) +{ + u32 l; + + l = sms_read_reg(SMS_SYSCONFIG); + l &= ~(0x3 << 3); + l |= (0x2 << 3); + sms_write_reg(l, SMS_SYSCONFIG); + + l = sdrc_read_reg(SDRC_SYSCONFIG); + l &= ~(0x3 << 3); + l |= (0x2 << 3); + sdrc_write_reg(l, SDRC_SYSCONFIG); + + sdrc_init_params = sp; +} |