mfd: syscon: atmel-smc: Add new helpers to ease SMC regs manipulation
authorBoris Brezillon <boris.brezillon@free-electrons.com>
Thu, 16 Mar 2017 08:30:28 +0000 (09:30 +0100)
committerLee Jones <lee.jones@linaro.org>
Thu, 27 Apr 2017 08:25:05 +0000 (09:25 +0100)
These new helpers + macro definitions are meant to replace the old ones
which are unpractical to use.

Note that the macros and function prefixes have been intentionally
changed to ATMEL_[H]SMC_XX and atmel_[h]smc_ to reflect the fact that
this IP is also embedded in avr32 SoCs (and not only in at91 ones).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
drivers/mfd/Kconfig
drivers/mfd/Makefile
drivers/mfd/atmel-smc.c [new file with mode: 0644]
include/linux/mfd/syscon/atmel-smc.h

index add0c35c38c5e33127b19a037ab7c79fbca5dd4d..ce3a9180a765f32fae06b1a77ce4544b8b16c457 100644 (file)
@@ -121,6 +121,10 @@ config MFD_ATMEL_HLCDC
          additional drivers must be enabled in order to use the
          functionality of the device.
 
+config MFD_ATMEL_SMC
+       bool
+       select MFD_SYSCON
+
 config MFD_BCM590XX
        tristate "Broadcom BCM590xx PMUs"
        select MFD_CORE
index 294a0525aeb16f75abe13a48106828b99f3e0fbc..fa86dbe65e52115dbcad3379f17d0f8a61cbd366 100644 (file)
@@ -185,6 +185,7 @@ obj-$(CONFIG_MFD_TPS65090)  += tps65090.o
 obj-$(CONFIG_MFD_AAT2870_CORE) += aat2870-core.o
 obj-$(CONFIG_MFD_ATMEL_FLEXCOM)        += atmel-flexcom.o
 obj-$(CONFIG_MFD_ATMEL_HLCDC)  += atmel-hlcdc.o
+obj-$(CONFIG_MFD_ATMEL_SMC)    += atmel-smc.o
 obj-$(CONFIG_MFD_INTEL_LPSS)   += intel-lpss.o
 obj-$(CONFIG_MFD_INTEL_LPSS_PCI)       += intel-lpss-pci.o
 obj-$(CONFIG_MFD_INTEL_LPSS_ACPI)      += intel-lpss-acpi.o
diff --git a/drivers/mfd/atmel-smc.c b/drivers/mfd/atmel-smc.c
new file mode 100644 (file)
index 0000000..954cf0f
--- /dev/null
@@ -0,0 +1,314 @@
+/*
+ * Atmel SMC (Static Memory Controller) helper functions.
+ *
+ * Copyright (C) 2017 Atmel
+ * Copyright (C) 2017 Free Electrons
+ *
+ * Author: Boris Brezillon <boris.brezillon@free-electrons.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.
+ */
+
+#include <linux/mfd/syscon/atmel-smc.h>
+
+/**
+ * atmel_smc_cs_conf_init - initialize a SMC CS conf
+ * @conf: the SMC CS conf to initialize
+ *
+ * Set all fields to 0 so that one can start defining a new config.
+ */
+void atmel_smc_cs_conf_init(struct atmel_smc_cs_conf *conf)
+{
+       memset(conf, 0, sizeof(*conf));
+}
+EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_init);
+
+/**
+ * atmel_smc_cs_encode_ncycles - encode a number of MCK clk cycles in the
+ *                              format expected by the SMC engine
+ * @ncycles: number of MCK clk cycles
+ * @msbpos: position of the MSB part of the timing field
+ * @msbwidth: width of the MSB part of the timing field
+ * @msbfactor: factor applied to the MSB
+ * @encodedval: param used to store the encoding result
+ *
+ * This function encodes the @ncycles value as described in the datasheet
+ * (section "SMC Setup/Pulse/Cycle/Timings Register"). This is a generic
+ * helper which called with different parameter depending on the encoding
+ * scheme.
+ *
+ * If the @ncycles value is too big to be encoded, -ERANGE is returned and
+ * the encodedval is contains the maximum val. Otherwise, 0 is returned.
+ */
+static int atmel_smc_cs_encode_ncycles(unsigned int ncycles,
+                                      unsigned int msbpos,
+                                      unsigned int msbwidth,
+                                      unsigned int msbfactor,
+                                      unsigned int *encodedval)
+{
+       unsigned int lsbmask = GENMASK(msbpos - 1, 0);
+       unsigned int msbmask = GENMASK(msbwidth - 1, 0);
+       unsigned int msb, lsb;
+       int ret = 0;
+
+       msb = ncycles / msbfactor;
+       lsb = ncycles % msbfactor;
+
+       if (lsb > lsbmask) {
+               lsb = 0;
+               msb++;
+       }
+
+       /*
+        * Let's just put the maximum we can if the requested setting does
+        * not fit in the register field.
+        * We still return -ERANGE in case the caller cares.
+        */
+       if (msb > msbmask) {
+               msb = msbmask;
+               lsb = lsbmask;
+               ret = -ERANGE;
+       }
+
+       *encodedval = (msb << msbpos) | lsb;
+
+       return ret;
+}
+
+/**
+ * atmel_smc_cs_conf_set_timing - set the SMC CS conf Txx parameter to a
+ *                               specific value
+ * @conf: SMC CS conf descriptor
+ * @shift: the position of the Txx field in the TIMINGS register
+ * @ncycles: value (expressed in MCK clk cycles) to assign to this Txx
+ *          parameter
+ *
+ * This function encodes the @ncycles value as described in the datasheet
+ * (section "SMC Timings Register"), and then stores the result in the
+ * @conf->timings field at @shift position.
+ *
+ * Returns -EINVAL if shift is invalid, -ERANGE if ncycles does not fit in
+ * the field, and 0 otherwise.
+ */
+int atmel_smc_cs_conf_set_timing(struct atmel_smc_cs_conf *conf,
+                                unsigned int shift, unsigned int ncycles)
+{
+       unsigned int val;
+       int ret;
+
+       if (shift != ATMEL_HSMC_TIMINGS_TCLR_SHIFT &&
+           shift != ATMEL_HSMC_TIMINGS_TADL_SHIFT &&
+           shift != ATMEL_HSMC_TIMINGS_TAR_SHIFT &&
+           shift != ATMEL_HSMC_TIMINGS_TRR_SHIFT &&
+           shift != ATMEL_HSMC_TIMINGS_TWB_SHIFT)
+               return -EINVAL;
+
+       /*
+        * The formula described in atmel datasheets (section "HSMC Timings
+        * Register"):
+        *
+        * ncycles = (Txx[3] * 64) + Txx[2:0]
+        */
+       ret = atmel_smc_cs_encode_ncycles(ncycles, 3, 1, 64, &val);
+       conf->timings &= ~GENMASK(shift + 3, shift);
+       conf->timings |= val << shift;
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_set_timing);
+
+/**
+ * atmel_smc_cs_conf_set_setup - set the SMC CS conf xx_SETUP parameter to a
+ *                              specific value
+ * @conf: SMC CS conf descriptor
+ * @shift: the position of the xx_SETUP field in the SETUP register
+ * @ncycles: value (expressed in MCK clk cycles) to assign to this xx_SETUP
+ *          parameter
+ *
+ * This function encodes the @ncycles value as described in the datasheet
+ * (section "SMC Setup Register"), and then stores the result in the
+ * @conf->setup field at @shift position.
+ *
+ * Returns -EINVAL if @shift is invalid, -ERANGE if @ncycles does not fit in
+ * the field, and 0 otherwise.
+ */
+int atmel_smc_cs_conf_set_setup(struct atmel_smc_cs_conf *conf,
+                               unsigned int shift, unsigned int ncycles)
+{
+       unsigned int val;
+       int ret;
+
+       if (shift != ATMEL_SMC_NWE_SHIFT && shift != ATMEL_SMC_NCS_WR_SHIFT &&
+           shift != ATMEL_SMC_NRD_SHIFT && shift != ATMEL_SMC_NCS_RD_SHIFT)
+               return -EINVAL;
+
+       /*
+        * The formula described in atmel datasheets (section "SMC Setup
+        * Register"):
+        *
+        * ncycles = (128 * xx_SETUP[5]) + xx_SETUP[4:0]
+        */
+       ret = atmel_smc_cs_encode_ncycles(ncycles, 5, 1, 128, &val);
+       conf->setup &= ~GENMASK(shift + 7, shift);
+       conf->setup |= val << shift;
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_set_setup);
+
+/**
+ * atmel_smc_cs_conf_set_pulse - set the SMC CS conf xx_PULSE parameter to a
+ *                              specific value
+ * @conf: SMC CS conf descriptor
+ * @shift: the position of the xx_PULSE field in the PULSE register
+ * @ncycles: value (expressed in MCK clk cycles) to assign to this xx_PULSE
+ *          parameter
+ *
+ * This function encodes the @ncycles value as described in the datasheet
+ * (section "SMC Pulse Register"), and then stores the result in the
+ * @conf->setup field at @shift position.
+ *
+ * Returns -EINVAL if @shift is invalid, -ERANGE if @ncycles does not fit in
+ * the field, and 0 otherwise.
+ */
+int atmel_smc_cs_conf_set_pulse(struct atmel_smc_cs_conf *conf,
+                               unsigned int shift, unsigned int ncycles)
+{
+       unsigned int val;
+       int ret;
+
+       if (shift != ATMEL_SMC_NWE_SHIFT && shift != ATMEL_SMC_NCS_WR_SHIFT &&
+           shift != ATMEL_SMC_NRD_SHIFT && shift != ATMEL_SMC_NCS_RD_SHIFT)
+               return -EINVAL;
+
+       /*
+        * The formula described in atmel datasheets (section "SMC Pulse
+        * Register"):
+        *
+        * ncycles = (256 * xx_PULSE[6]) + xx_PULSE[5:0]
+        */
+       ret = atmel_smc_cs_encode_ncycles(ncycles, 6, 1, 256, &val);
+       conf->pulse &= ~GENMASK(shift + 7, shift);
+       conf->pulse |= val << shift;
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_set_pulse);
+
+/**
+ * atmel_smc_cs_conf_set_cycle - set the SMC CS conf xx_CYCLE parameter to a
+ *                              specific value
+ * @conf: SMC CS conf descriptor
+ * @shift: the position of the xx_CYCLE field in the CYCLE register
+ * @ncycles: value (expressed in MCK clk cycles) to assign to this xx_CYCLE
+ *          parameter
+ *
+ * This function encodes the @ncycles value as described in the datasheet
+ * (section "SMC Pulse Register"), and then stores the result in the
+ * @conf->setup field at @shift position.
+ *
+ * Returns -EINVAL if @shift is invalid, -ERANGE if @ncycles does not fit in
+ * the field, and 0 otherwise.
+ */
+int atmel_smc_cs_conf_set_cycle(struct atmel_smc_cs_conf *conf,
+                               unsigned int shift, unsigned int ncycles)
+{
+       unsigned int val;
+       int ret;
+
+       if (shift != ATMEL_SMC_NWE_SHIFT && shift != ATMEL_SMC_NRD_SHIFT)
+               return -EINVAL;
+
+       /*
+        * The formula described in atmel datasheets (section "SMC Cycle
+        * Register"):
+        *
+        * ncycles = (xx_CYCLE[8:7] * 256) + xx_CYCLE[6:0]
+        */
+       ret = atmel_smc_cs_encode_ncycles(ncycles, 7, 2, 256, &val);
+       conf->cycle &= ~GENMASK(shift + 15, shift);
+       conf->cycle |= val << shift;
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_set_cycle);
+
+/**
+ * atmel_smc_cs_conf_apply - apply an SMC CS conf
+ * @regmap: the SMC regmap
+ * @cs: the CS id
+ * @conf the SMC CS conf to apply
+ *
+ * Applies an SMC CS configuration.
+ * Only valid on at91sam9/avr32 SoCs.
+ */
+void atmel_smc_cs_conf_apply(struct regmap *regmap, int cs,
+                            const struct atmel_smc_cs_conf *conf)
+{
+       regmap_write(regmap, ATMEL_SMC_SETUP(cs), conf->setup);
+       regmap_write(regmap, ATMEL_SMC_PULSE(cs), conf->pulse);
+       regmap_write(regmap, ATMEL_SMC_CYCLE(cs), conf->cycle);
+       regmap_write(regmap, ATMEL_SMC_MODE(cs), conf->mode);
+}
+EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_apply);
+
+/**
+ * atmel_hsmc_cs_conf_apply - apply an SMC CS conf
+ * @regmap: the HSMC regmap
+ * @cs: the CS id
+ * @conf the SMC CS conf to apply
+ *
+ * Applies an SMC CS configuration.
+ * Only valid on post-sama5 SoCs.
+ */
+void atmel_hsmc_cs_conf_apply(struct regmap *regmap, int cs,
+                             const struct atmel_smc_cs_conf *conf)
+{
+       regmap_write(regmap, ATMEL_HSMC_SETUP(cs), conf->setup);
+       regmap_write(regmap, ATMEL_HSMC_PULSE(cs), conf->pulse);
+       regmap_write(regmap, ATMEL_HSMC_CYCLE(cs), conf->cycle);
+       regmap_write(regmap, ATMEL_HSMC_TIMINGS(cs), conf->timings);
+       regmap_write(regmap, ATMEL_HSMC_MODE(cs), conf->mode);
+}
+EXPORT_SYMBOL_GPL(atmel_hsmc_cs_conf_apply);
+
+/**
+ * atmel_smc_cs_conf_get - retrieve the current SMC CS conf
+ * @regmap: the SMC regmap
+ * @cs: the CS id
+ * @conf: the SMC CS conf object to store the current conf
+ *
+ * Retrieve the SMC CS configuration.
+ * Only valid on at91sam9/avr32 SoCs.
+ */
+void atmel_smc_cs_conf_get(struct regmap *regmap, int cs,
+                          struct atmel_smc_cs_conf *conf)
+{
+       regmap_read(regmap, ATMEL_SMC_SETUP(cs), &conf->setup);
+       regmap_read(regmap, ATMEL_SMC_PULSE(cs), &conf->pulse);
+       regmap_read(regmap, ATMEL_SMC_CYCLE(cs), &conf->cycle);
+       regmap_read(regmap, ATMEL_SMC_MODE(cs), &conf->mode);
+}
+EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_get);
+
+/**
+ * atmel_hsmc_cs_conf_get - retrieve the current SMC CS conf
+ * @regmap: the HSMC regmap
+ * @cs: the CS id
+ * @conf: the SMC CS conf object to store the current conf
+ *
+ * Retrieve the SMC CS configuration.
+ * Only valid on post-sama5 SoCs.
+ */
+void atmel_hsmc_cs_conf_get(struct regmap *regmap, int cs,
+                           struct atmel_smc_cs_conf *conf)
+{
+       regmap_read(regmap, ATMEL_HSMC_SETUP(cs), &conf->setup);
+       regmap_read(regmap, ATMEL_HSMC_PULSE(cs), &conf->pulse);
+       regmap_read(regmap, ATMEL_HSMC_CYCLE(cs), &conf->cycle);
+       regmap_read(regmap, ATMEL_HSMC_TIMINGS(cs), &conf->timings);
+       regmap_read(regmap, ATMEL_HSMC_MODE(cs), &conf->mode);
+}
+EXPORT_SYMBOL_GPL(atmel_hsmc_cs_conf_get);
index be6ebe64eebe1964573a2b963004a8055dff7abf..00e6e3c8ee6f80b31d2b107abaf23ca385e18bbe 100644 (file)
 #define AT91_SMC_PS_16                 (2 << 28)
 #define AT91_SMC_PS_32                 (3 << 28)
 
+#define ATMEL_SMC_SETUP(cs)                    (((cs) * 0x10))
+#define ATMEL_HSMC_SETUP(cs)                   (0x600 + ((cs) * 0x14))
+#define ATMEL_SMC_PULSE(cs)                    (((cs) * 0x10) + 0x4)
+#define ATMEL_HSMC_PULSE(cs)                   (0x600 + ((cs) * 0x14) + 0x4)
+#define ATMEL_SMC_CYCLE(cs)                    (((cs) * 0x10) + 0x8)
+#define ATMEL_HSMC_CYCLE(cs)                   (0x600 + ((cs) * 0x14) + 0x8)
+#define ATMEL_SMC_NWE_SHIFT                    0
+#define ATMEL_SMC_NCS_WR_SHIFT                 8
+#define ATMEL_SMC_NRD_SHIFT                    16
+#define ATMEL_SMC_NCS_RD_SHIFT                 24
+
+#define ATMEL_SMC_MODE(cs)                     (((cs) * 0x10) + 0xc)
+#define ATMEL_HSMC_MODE(cs)                    (0x600 + ((cs) * 0x14) + 0x10)
+#define ATMEL_SMC_MODE_READMODE_MASK           BIT(0)
+#define ATMEL_SMC_MODE_READMODE_NCS            (0 << 0)
+#define ATMEL_SMC_MODE_READMODE_NRD            (1 << 0)
+#define ATMEL_SMC_MODE_WRITEMODE_MASK          BIT(1)
+#define ATMEL_SMC_MODE_WRITEMODE_NCS           (0 << 1)
+#define ATMEL_SMC_MODE_WRITEMODE_NWE           (1 << 1)
+#define ATMEL_SMC_MODE_EXNWMODE_MASK           GENMASK(5, 4)
+#define ATMEL_SMC_MODE_EXNWMODE_DISABLE                (0 << 4)
+#define ATMEL_SMC_MODE_EXNWMODE_FROZEN         (2 << 4)
+#define ATMEL_SMC_MODE_EXNWMODE_READY          (3 << 4)
+#define ATMEL_SMC_MODE_BAT_MASK                        BIT(8)
+#define ATMEL_SMC_MODE_BAT_SELECT              (0 << 8)
+#define ATMEL_SMC_MODE_BAT_WRITE               (1 << 8)
+#define ATMEL_SMC_MODE_DBW_MASK                        GENMASK(13, 12)
+#define ATMEL_SMC_MODE_DBW_8                   (0 << 12)
+#define ATMEL_SMC_MODE_DBW_16                  (1 << 12)
+#define ATMEL_SMC_MODE_DBW_32                  (2 << 12)
+#define ATMEL_SMC_MODE_TDF_MASK                        GENMASK(19, 16)
+#define ATMEL_SMC_MODE_TDF(x)                  (((x) - 1) << 16)
+#define ATMEL_SMC_MODE_TDF_MAX                 16
+#define ATMEL_SMC_MODE_TDF_MIN                 1
+#define ATMEL_SMC_MODE_TDFMODE_OPTIMIZED       BIT(20)
+#define ATMEL_SMC_MODE_PMEN                    BIT(24)
+#define ATMEL_SMC_MODE_PS_MASK                 GENMASK(29, 28)
+#define ATMEL_SMC_MODE_PS_4                    (0 << 28)
+#define ATMEL_SMC_MODE_PS_8                    (1 << 28)
+#define ATMEL_SMC_MODE_PS_16                   (2 << 28)
+#define ATMEL_SMC_MODE_PS_32                   (3 << 28)
+
+#define ATMEL_HSMC_TIMINGS(cs)                 (0x600 + ((cs) * 0x14) + 0xc)
+#define ATMEL_HSMC_TIMINGS_OCMS                        BIT(12)
+#define ATMEL_HSMC_TIMINGS_RBNSEL(x)           ((x) << 28)
+#define ATMEL_HSMC_TIMINGS_NFSEL               BIT(31)
+#define ATMEL_HSMC_TIMINGS_TCLR_SHIFT          0
+#define ATMEL_HSMC_TIMINGS_TADL_SHIFT          4
+#define ATMEL_HSMC_TIMINGS_TAR_SHIFT           8
+#define ATMEL_HSMC_TIMINGS_TRR_SHIFT           16
+#define ATMEL_HSMC_TIMINGS_TWB_SHIFT           24
+
+/**
+ * struct atmel_smc_cs_conf - SMC CS config as described in the datasheet.
+ * @setup: NCS/NWE/NRD setup timings (not applicable to at91rm9200)
+ * @pulse: NCS/NWE/NRD pulse timings (not applicable to at91rm9200)
+ * @cycle: NWE/NRD cycle timings (not applicable to at91rm9200)
+ * @timings: advanced NAND related timings (only applicable to HSMC)
+ * @mode: all kind of config parameters (see the fields definition above).
+ *       The mode fields are different on at91rm9200
+ */
+struct atmel_smc_cs_conf {
+       u32 setup;
+       u32 pulse;
+       u32 cycle;
+       u32 timings;
+       u32 mode;
+};
+
+void atmel_smc_cs_conf_init(struct atmel_smc_cs_conf *conf);
+int atmel_smc_cs_conf_set_timing(struct atmel_smc_cs_conf *conf,
+                                unsigned int shift,
+                                unsigned int ncycles);
+int atmel_smc_cs_conf_set_setup(struct atmel_smc_cs_conf *conf,
+                               unsigned int shift, unsigned int ncycles);
+int atmel_smc_cs_conf_set_pulse(struct atmel_smc_cs_conf *conf,
+                               unsigned int shift, unsigned int ncycles);
+int atmel_smc_cs_conf_set_cycle(struct atmel_smc_cs_conf *conf,
+                               unsigned int shift, unsigned int ncycles);
+void atmel_smc_cs_conf_apply(struct regmap *regmap, int cs,
+                            const struct atmel_smc_cs_conf *conf);
+void atmel_hsmc_cs_conf_apply(struct regmap *regmap, int cs,
+                             const struct atmel_smc_cs_conf *conf);
+void atmel_smc_cs_conf_get(struct regmap *regmap, int cs,
+                          struct atmel_smc_cs_conf *conf);
+void atmel_hsmc_cs_conf_get(struct regmap *regmap, int cs,
+                           struct atmel_smc_cs_conf *conf);
 
 /*
  * This function converts a setup timing expressed in nanoseconds into an