diff options
Diffstat (limited to 'arch/arm/cpu/armv7/omap4/emif.c')
-rw-r--r-- | arch/arm/cpu/armv7/omap4/emif.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/omap4/emif.c b/arch/arm/cpu/armv7/omap4/emif.c new file mode 100644 index 0000000000..ca4823dd79 --- /dev/null +++ b/arch/arm/cpu/armv7/omap4/emif.c @@ -0,0 +1,129 @@ +/* + * EMIF programming + * + * (C) Copyright 2010 + * Texas Instruments, <www.ti.com> + * + * Aneesh V <aneesh@ti.com> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <asm/emif.h> +#include <asm/arch/sys_proto.h> +#include <asm/utils.h> + +#ifndef CONFIG_SYS_EMIF_PRECALCULATED_TIMING_REGS +u32 *const T_num = (u32 *)OMAP4_SRAM_SCRATCH_EMIF_T_NUM; +u32 *const T_den = (u32 *)OMAP4_SRAM_SCRATCH_EMIF_T_DEN; +u32 *const emif_sizes = (u32 *)OMAP4_SRAM_SCRATCH_EMIF_SIZE; +#endif + +#ifdef CONFIG_SYS_DEFAULT_LPDDR2_TIMINGS +/* Base AC Timing values specified by JESD209-2 for 400MHz operation */ +static const struct lpddr2_ac_timings timings_jedec_400_mhz = { + .max_freq = 400000000, + .RL = 6, + .tRPab = 21, + .tRCD = 18, + .tWR = 15, + .tRASmin = 42, + .tRRD = 10, + .tWTRx2 = 15, + .tXSR = 140, + .tXPx2 = 15, + .tRFCab = 130, + .tRTPx2 = 15, + .tCKE = 3, + .tCKESR = 15, + .tZQCS = 90, + .tZQCL = 360, + .tZQINIT = 1000, + .tDQSCKMAXx2 = 11, + .tRASmax = 70, + .tFAW = 50 +}; + +/* Base AC Timing values specified by JESD209-2 for 200 MHz operation */ +static const struct lpddr2_ac_timings timings_jedec_200_mhz = { + .max_freq = 200000000, + .RL = 3, + .tRPab = 21, + .tRCD = 18, + .tWR = 15, + .tRASmin = 42, + .tRRD = 10, + .tWTRx2 = 20, + .tXSR = 140, + .tXPx2 = 15, + .tRFCab = 130, + .tRTPx2 = 15, + .tCKE = 3, + .tCKESR = 15, + .tZQCS = 90, + .tZQCL = 360, + .tZQINIT = 1000, + .tDQSCKMAXx2 = 11, + .tRASmax = 70, + .tFAW = 50 +}; + +/* + * Min tCK values specified by JESD209-2 + * Min tCK specifies the minimum duration of some AC timing parameters in terms + * of the number of cycles. If the calculated number of cycles based on the + * absolute time value is less than the min tCK value, min tCK value should + * be used instead. This typically happens at low frequencies. + */ +static const struct lpddr2_min_tck min_tck_jedec = { + .tRL = 3, + .tRP_AB = 3, + .tRCD = 3, + .tWR = 3, + .tRAS_MIN = 3, + .tRRD = 2, + .tWTR = 2, + .tXP = 2, + .tRTP = 2, + .tCKE = 3, + .tCKESR = 3, + .tFAW = 8 +}; + +static const struct lpddr2_ac_timings const* + jedec_ac_timings[MAX_NUM_SPEEDBINS] = { + &timings_jedec_200_mhz, + &timings_jedec_400_mhz +}; + +static const struct lpddr2_device_timings jedec_default_timings = { + .ac_timings = jedec_ac_timings, + .min_tck = &min_tck_jedec +}; + +void emif_get_device_timings(u32 emif_nr, + const struct lpddr2_device_timings **cs0_device_timings, + const struct lpddr2_device_timings **cs1_device_timings) +{ + /* Assume Identical devices on EMIF1 & EMIF2 */ + *cs0_device_timings = &jedec_default_timings; + *cs1_device_timings = &jedec_default_timings; +} +#endif /* CONFIG_SYS_DEFAULT_LPDDR2_TIMINGS */ |