Atmel AT91 SoCs have a memory range reserved for SMC (Static Memory Controller) configuration. Expose those registers so that drivers can make use of the smc syscon declared in at91 DTs. Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> Acked-by: Lee Jones <lee.jones@xxxxxxxxxx> --- include/linux/mfd/syscon/atmel-smc.h | 173 +++++++++++++++++++++++++++++++++++ 1 file changed, 173 insertions(+) create mode 100644 include/linux/mfd/syscon/atmel-smc.h diff --git a/include/linux/mfd/syscon/atmel-smc.h b/include/linux/mfd/syscon/atmel-smc.h new file mode 100644 index 0000000..be6ebe6 --- /dev/null +++ b/include/linux/mfd/syscon/atmel-smc.h @@ -0,0 +1,173 @@ +/* + * Atmel SMC (Static Memory Controller) register offsets and bit definitions. + * + * Copyright (C) 2014 Atmel + * Copyright (C) 2014 Free Electrons + * + * Author: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> + * + * 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. + */ + +#ifndef _LINUX_MFD_SYSCON_ATMEL_SMC_H_ +#define _LINUX_MFD_SYSCON_ATMEL_SMC_H_ + +#include <linux/kernel.h> +#include <linux/regmap.h> + +#define AT91SAM9_SMC_GENERIC 0x00 +#define AT91SAM9_SMC_GENERIC_BLK_SZ 0x10 + +#define SAMA5_SMC_GENERIC 0x600 +#define SAMA5_SMC_GENERIC_BLK_SZ 0x14 + +#define AT91SAM9_SMC_SETUP(o) ((o) + 0x00) +#define AT91SAM9_SMC_NWESETUP(x) (x) +#define AT91SAM9_SMC_NCS_WRSETUP(x) ((x) << 8) +#define AT91SAM9_SMC_NRDSETUP(x) ((x) << 16) +#define AT91SAM9_SMC_NCS_NRDSETUP(x) ((x) << 24) + +#define AT91SAM9_SMC_PULSE(o) ((o) + 0x04) +#define AT91SAM9_SMC_NWEPULSE(x) (x) +#define AT91SAM9_SMC_NCS_WRPULSE(x) ((x) << 8) +#define AT91SAM9_SMC_NRDPULSE(x) ((x) << 16) +#define AT91SAM9_SMC_NCS_NRDPULSE(x) ((x) << 24) + +#define AT91SAM9_SMC_CYCLE(o) ((o) + 0x08) +#define AT91SAM9_SMC_NWECYCLE(x) (x) +#define AT91SAM9_SMC_NRDCYCLE(x) ((x) << 16) + +#define AT91SAM9_SMC_MODE(o) ((o) + 0x0c) +#define SAMA5_SMC_MODE(o) ((o) + 0x10) +#define AT91_SMC_READMODE BIT(0) +#define AT91_SMC_READMODE_NCS (0 << 0) +#define AT91_SMC_READMODE_NRD (1 << 0) +#define AT91_SMC_WRITEMODE BIT(1) +#define AT91_SMC_WRITEMODE_NCS (0 << 1) +#define AT91_SMC_WRITEMODE_NWE (1 << 1) +#define AT91_SMC_EXNWMODE GENMASK(5, 4) +#define AT91_SMC_EXNWMODE_DISABLE (0 << 4) +#define AT91_SMC_EXNWMODE_FROZEN (2 << 4) +#define AT91_SMC_EXNWMODE_READY (3 << 4) +#define AT91_SMC_BAT BIT(8) +#define AT91_SMC_BAT_SELECT (0 << 8) +#define AT91_SMC_BAT_WRITE (1 << 8) +#define AT91_SMC_DBW GENMASK(13, 12) +#define AT91_SMC_DBW_8 (0 << 12) +#define AT91_SMC_DBW_16 (1 << 12) +#define AT91_SMC_DBW_32 (2 << 12) +#define AT91_SMC_TDF GENMASK(19, 16) +#define AT91_SMC_TDF_(x) ((((x) - 1) << 16) & AT91_SMC_TDF) +#define AT91_SMC_TDF_MAX 16 +#define AT91_SMC_TDFMODE_OPTIMIZED BIT(20) +#define AT91_SMC_PMEN BIT(24) +#define AT91_SMC_PS GENMASK(29, 28) +#define AT91_SMC_PS_4 (0 << 28) +#define AT91_SMC_PS_8 (1 << 28) +#define AT91_SMC_PS_16 (2 << 28) +#define AT91_SMC_PS_32 (3 << 28) + + +/* + * This function converts a setup timing expressed in nanoseconds into an + * encoded value that can be written in the SMC_SETUP register. + * + * The following formula is described in atmel datasheets (section + * "SMC Setup Register"): + * + * setup length = (128* SETUP[5] + SETUP[4:0]) + * + * where setup length is the timing expressed in cycles. + */ +static inline u32 at91sam9_smc_setup_ns_to_cycles(unsigned int clk_rate, + u32 timing_ns) +{ + u32 clk_period = DIV_ROUND_UP(NSEC_PER_SEC, clk_rate); + u32 coded_cycles = 0; + u32 cycles; + + cycles = DIV_ROUND_UP(timing_ns, clk_period); + if (cycles / 32) { + coded_cycles |= 1 << 5; + if (cycles < 128) + cycles = 0; + } + + coded_cycles |= cycles % 32; + + return coded_cycles; +} + +/* + * This function converts a pulse timing expressed in nanoseconds into an + * encoded value that can be written in the SMC_PULSE register. + * + * The following formula is described in atmel datasheets (section + * "SMC Pulse Register"): + * + * pulse length = (256* PULSE[6] + PULSE[5:0]) + * + * where pulse length is the timing expressed in cycles. + */ +static inline u32 at91sam9_smc_pulse_ns_to_cycles(unsigned int clk_rate, + u32 timing_ns) +{ + u32 clk_period = DIV_ROUND_UP(NSEC_PER_SEC, clk_rate); + u32 coded_cycles = 0; + u32 cycles; + + cycles = DIV_ROUND_UP(timing_ns, clk_period); + if (cycles / 64) { + coded_cycles |= 1 << 6; + if (cycles < 256) + cycles = 0; + } + + coded_cycles |= cycles % 64; + + return coded_cycles; +} + +/* + * This function converts a cycle timing expressed in nanoseconds into an + * encoded value that can be written in the SMC_CYCLE register. + * + * The following formula is described in atmel datasheets (section + * "SMC Cycle Register"): + * + * cycle length = (CYCLE[8:7]*256 + CYCLE[6:0]) + * + * where cycle length is the timing expressed in cycles. + */ +static inline u32 at91sam9_smc_cycle_ns_to_cycles(unsigned int clk_rate, + u32 timing_ns) +{ + u32 clk_period = DIV_ROUND_UP(NSEC_PER_SEC, clk_rate); + u32 coded_cycles = 0; + u32 cycles; + + cycles = DIV_ROUND_UP(timing_ns, clk_period); + if (cycles / 128) { + coded_cycles = cycles / 256; + cycles %= 256; + if (cycles >= 128) { + coded_cycles++; + cycles = 0; + } + + if (coded_cycles > 0x3) { + coded_cycles = 0x3; + cycles = 0x7f; + } + + coded_cycles <<= 7; + } + + coded_cycles |= cycles % 128; + + return coded_cycles; +} + +#endif /* _LINUX_MFD_SYSCON_ATMEL_SMC_H_ */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html