clk: Add MPC83xx clock driver

Add a clock driver for the MPC83xx architecture.

Signed-off-by: Mario Six <mario.six@gdsys.cc>

1 files changed, 379 insertions, 0 deletions

diff --git a/drivers/clk/mpc83xx_clk.h b/drivers/clk/mpc83xx_clk.h
new file mode 100644
index 0000000000..7fb8802920
--- /dev/null
+++ b/drivers/clk/mpc83xx_clk.h
@@ -0,0 +1,379 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2018
+ * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
+ */
+
+/**
+ * enum ratio - Description of a core clock ratio
+ * @RAT_UNK:      Unknown ratio
+ * @RAT_BYP:      Bypass
+ * @RAT_1_TO_8:   Ratio 1:8
+ * @RAT_1_TO_4:   Ratio 1:4
+ * @RAT_1_TO_2:   Ratio 1:2
+ * @RAT_1_TO_1:   Ratio 1:1
+ * @RAT_1_5_TO_1: Ratio 1.5:1
+ * @RAT_2_TO_1:   Ratio 2:1
+ * @RAT_2_5_TO_1: Ratio 2.5:1
+ * @RAT_3_TO_1:   Ratio 3:1
+ */
+enum ratio {
+	RAT_UNK,
+	RAT_BYP,
+	RAT_1_TO_8,
+	RAT_1_TO_4,
+	RAT_1_TO_2,
+	RAT_1_TO_1,
+	RAT_1_5_TO_1,
+	RAT_2_TO_1,
+	RAT_2_5_TO_1,
+	RAT_3_TO_1
+};
+
+/**
+ * struct corecnf - Description for a core clock configuration
+ * @core_csb_ratio: Core clock frequency to CSB clock frequency ratio
+ * @vco_divider: VCO divider (Core VCO frequency = Core frequency * VCO divider)
+ */
+struct corecnf {
+	int core_csb_ratio;
+	int vco_divider;
+};
+
+/*
+ * Table with all valid Core CSB frequency ratio / VCO divider combinations as
+ * indexed by the COREPLL field of the SPMR
+ */
+static const struct corecnf corecnf_tab[] = {
+	{RAT_BYP, RAT_BYP},			/* 0x00 */
+	{RAT_BYP, RAT_BYP},			/* 0x01 */
+	{RAT_BYP, RAT_BYP},			/* 0x02 */
+	{RAT_BYP, RAT_BYP},			/* 0x03 */
+	{RAT_BYP, RAT_BYP},			/* 0x04 */
+	{RAT_BYP, RAT_BYP},			/* 0x05 */
+	{RAT_BYP, RAT_BYP},			/* 0x06 */
+	{RAT_BYP, RAT_BYP},			/* 0x07 */
+	{RAT_1_TO_1, RAT_1_TO_2},		/* 0x08 */
+	{RAT_1_TO_1, RAT_1_TO_4},		/* 0x09 */
+	{RAT_1_TO_1, RAT_1_TO_8},		/* 0x0A */
+	{RAT_1_TO_1, RAT_1_TO_8},		/* 0x0B */
+	{RAT_1_5_TO_1, RAT_1_TO_2},		/* 0x0C */
+	{RAT_1_5_TO_1, RAT_1_TO_4},		/* 0x0D */
+	{RAT_1_5_TO_1, RAT_1_TO_8},		/* 0x0E */
+	{RAT_1_5_TO_1, RAT_1_TO_8},		/* 0x0F */
+	{RAT_2_TO_1, RAT_1_TO_2},		/* 0x10 */
+	{RAT_2_TO_1, RAT_1_TO_4},		/* 0x11 */
+	{RAT_2_TO_1, RAT_1_TO_8},		/* 0x12 */
+	{RAT_2_TO_1, RAT_1_TO_8},		/* 0x13 */
+	{RAT_2_5_TO_1, RAT_1_TO_2},		/* 0x14 */
+	{RAT_2_5_TO_1, RAT_1_TO_4},		/* 0x15 */
+	{RAT_2_5_TO_1, RAT_1_TO_8},		/* 0x16 */
+	{RAT_2_5_TO_1, RAT_1_TO_8},		/* 0x17 */
+	{RAT_3_TO_1, RAT_1_TO_2},		/* 0x18 */
+	{RAT_3_TO_1, RAT_1_TO_4},		/* 0x19 */
+	{RAT_3_TO_1, RAT_1_TO_8},		/* 0x1A */
+	{RAT_3_TO_1, RAT_1_TO_8},		/* 0x1B */
+};
+
+/**
+ * enum reg_type - Register to read a field from
+ * @REG_SCCR: Use the SCCR register
+ * @REG_SPMR: Use the SPMR register
+ */
+enum reg_type {
+	REG_SCCR,
+	REG_SPMR,
+};
+
+/**
+ * enum mode_type - Description of how to read a specific frequency value
+ * @TYPE_INVALID: Unknown type, will provoke error
+ * @TYPE_SCCR_STANDARD:        Read a field from the SCCR register, and use it
+ *			       as a divider for the CSB clock to compute the
+ *			       frequency
+ * @TYPE_SCCR_ONOFF:           The field describes a bit flag that can turn the
+ *			       clock on or off
+ * @TYPE_SPMR_DIRECT_MULTIPLY: Read a field from the SPMR register, and use it
+ *			       as a multiplier for the CSB clock to compute the
+ *			       frequency
+ * @TYPE_SPECIAL:              The frequency is calculated in a non-standard way
+ */
+enum mode_type {
+	TYPE_INVALID = 0,
+	TYPE_SCCR_STANDARD,
+	TYPE_SCCR_ONOFF,
+	TYPE_SPMR_DIRECT_MULTIPLY,
+	TYPE_SPECIAL,
+};
+
+/* Map of each clock index to its human-readable name */
+static const char * const names[] = {
+	[MPC83XX_CLK_CORE] = "Core",
+	[MPC83XX_CLK_CSB] = "Coherent System Bus",
+	[MPC83XX_CLK_QE] = "QE",
+	[MPC83XX_CLK_BRG] = "BRG",
+	[MPC83XX_CLK_LBIU] = "Local Bus Controller",
+	[MPC83XX_CLK_LCLK] = "Local Bus",
+	[MPC83XX_CLK_MEM] = "DDR",
+	[MPC83XX_CLK_MEM_SEC] = "DDR Secondary",
+	[MPC83XX_CLK_ENC] = "SEC",
+	[MPC83XX_CLK_I2C1] = "I2C1",
+	[MPC83XX_CLK_I2C2] = "I2C2",
+	[MPC83XX_CLK_TDM] = "TDM",
+	[MPC83XX_CLK_SDHC] = "SDHC",
+	[MPC83XX_CLK_TSEC1] = "TSEC1",
+	[MPC83XX_CLK_TSEC2] = "TSEC2",
+	[MPC83XX_CLK_USBDR] = "USB DR",
+	[MPC83XX_CLK_USBMPH] = "USB MPH",
+	[MPC83XX_CLK_PCIEXP1] = "PCIEXP1",
+	[MPC83XX_CLK_PCIEXP2] = "PCIEXP2",
+	[MPC83XX_CLK_SATA] = "SATA",
+	[MPC83XX_CLK_DMAC] = "DMAC",
+	[MPC83XX_CLK_PCI] = "PCI",
+};
+
+/**
+ * struct clk_mode - Structure for clock mode descriiptions
+ * @low:  The low bit of the data field to read for this mode (may not apply to
+ *	  some modes)
+ * @high: The high bit of the data field to read for this mode (may not apply to
+ *	  some modes)
+ * @type: The type of the mode description (one of enum mode_type)
+ */
+struct clk_mode {
+	u8 low;
+	u8 high;
+	int type;
+};
+
+/**
+ * set_mode() - Build a clock mode description from data
+ * @mode: The clock mode description to be filled out
+ * @low:  The low bit of the data field to read for this mode (may not apply to
+ *	  some modes)
+ * @high: The high bit of the data field to read for this mode (may not apply to
+ *	  some modes)
+ * @type: The type of the mode description (one of enum mode_type)
+ *
+ * Clock mode descriptions are a succinct description of how to read a specific
+ * clock's rate from the hardware; usually by reading a specific field of a
+ * register, such a s the SCCR register, but some types use different methods
+ * for obtaining the clock rate.
+ */
+static void set_mode(struct clk_mode *mode, u8 low, u8 high, int type)
+{
+	mode->low = low;
+	mode->high = high;
+	mode->type = type;
+}
+
+/**
+ * retrieve_mode() - Get the clock mode description for a specific clock
+ * @clk:      The identifier of the clock for which the clock description should
+ *	      be retrieved
+ * @soc_type: The type of MPC83xx SoC for which the clock description should be
+ *	      retrieved
+ * @mode:     Pointer to a clk_mode structure to be filled with data for the
+ *	      clock
+ *
+ * Since some clock rate are stored in different places on different MPC83xx
+ * SoCs, the SoC type has to be supplied along with the clock's identifier.
+ *
+ * Return: 0 if OK, -ve on error
+ */
+static int retrieve_mode(int clk, int soc_type, struct clk_mode *mode)
+{
+	switch (clk) {
+	case MPC83XX_CLK_CORE:
+	case MPC83XX_CLK_CSB:
+	case MPC83XX_CLK_QE:
+	case MPC83XX_CLK_BRG:
+	case MPC83XX_CLK_LCLK:
+	case MPC83XX_CLK_I2C2:
+		set_mode(mode, 0, 0, TYPE_SPECIAL);
+		break;
+	case MPC83XX_CLK_MEM:
+		set_mode(mode, 1, 1, TYPE_SPMR_DIRECT_MULTIPLY);
+		break;
+	case MPC83XX_CLK_LBIU:
+	case MPC83XX_CLK_MEM_SEC:
+		set_mode(mode, 0, 0, TYPE_SPMR_DIRECT_MULTIPLY);
+		break;
+	case MPC83XX_CLK_TSEC1:
+		set_mode(mode, 0, 1, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_TSEC2:
+		if (soc_type == SOC_MPC8313) /* I2C and TSEC2 are the same register */
+			set_mode(mode, 2, 3, TYPE_SCCR_STANDARD);
+		else /* FIXME(mario.six@gdsys.cc): This has separate enable/disable bit! */
+			set_mode(mode, 0, 1, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_SDHC:
+		set_mode(mode, 4, 5, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_ENC:
+		set_mode(mode, 6, 7, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_I2C1:
+		if (soc_type == SOC_MPC8349)
+			set_mode(mode, 2, 3, TYPE_SCCR_STANDARD);
+		else /* I2C and ENC are the same register */
+			set_mode(mode, 6, 7, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_PCIEXP1:
+		set_mode(mode, 10, 11, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_PCIEXP2:
+		set_mode(mode, 12, 13, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_USBDR:
+		if (soc_type == SOC_MPC8313 || soc_type == SOC_MPC8349)
+			set_mode(mode, 10, 11, TYPE_SCCR_STANDARD);
+		else
+			set_mode(mode, 8, 9, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_USBMPH:
+		set_mode(mode, 8, 9, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_PCI:
+		set_mode(mode, 15, 15, TYPE_SCCR_ONOFF);
+		break;
+	case MPC83XX_CLK_DMAC:
+		set_mode(mode, 26, 27, TYPE_SCCR_STANDARD);
+		break;
+	case MPC83XX_CLK_SATA:
+		/* FIXME(mario.six@gdsys.cc): All SATA controllers must have the same clock ratio */
+		if (soc_type == SOC_MPC8379) {
+			set_mode(mode, 24, 25, TYPE_SCCR_STANDARD);
+			set_mode(mode, 26, 27, TYPE_SCCR_STANDARD);
+			set_mode(mode, 28, 29, TYPE_SCCR_STANDARD);
+			set_mode(mode, 30, 31, TYPE_SCCR_STANDARD);
+		} else {
+			set_mode(mode, 18, 19, TYPE_SCCR_STANDARD);
+			set_mode(mode, 20, 21, TYPE_SCCR_STANDARD);
+		}
+		break;
+	case MPC83XX_CLK_TDM:
+		set_mode(mode, 26, 27, TYPE_SCCR_STANDARD);
+		break;
+	default:
+		debug("%s: Unknown clock type %d on soc type %d\n",
+		      __func__, clk, soc_type);
+		set_mode(mode, 0, 0, TYPE_INVALID);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * get_spmr() - Read the SPMR (System PLL Mode Register)
+ * @im: Pointer to the MPC83xx main register map in question
+ *
+ * Return: The SPMR value as a 32-bit number.
+ */
+static inline u32 get_spmr(immap_t *im)
+{
+	u32 res = in_be32(&im->clk.spmr);
+
+	return res;
+}
+
+/**
+ * get_sccr() - Read the SCCR (System Clock Control Register)
+ * @im: Pointer to the MPC83xx main register map in question
+ *
+ * Return: The SCCR value as a 32-bit number.
+ */
+static inline u32 get_sccr(immap_t *im)
+{
+	u32 res = in_be32(&im->clk.sccr);
+
+	return res;
+}
+
+/**
+ * get_lcrr() - Read the LCRR (Clock Ratio Register)
+ * @im: Pointer to the MPC83xx main register map in question
+ *
+ * Return: The LCRR value as a 32-bit number.
+ */
+static inline u32 get_lcrr(immap_t *im)
+{
+	u32 res = in_be32(&im->im_lbc.lcrr);
+
+	return res;
+}
+
+/**
+ * get_pci_sync_in() - Read the PCI synchronization clock speed
+ * @im: Pointer to the MPC83xx main register map in question
+ *
+ * Return: The PCI synchronization clock speed value as a 32-bit number.
+ */
+static inline u32 get_pci_sync_in(immap_t *im)
+{
+	u8 clkin_div;
+
+	clkin_div = (get_spmr(im) & SPMR_CKID) >> SPMR_CKID_SHIFT;
+	return CONFIG_SYS_CLK_FREQ / (1 + clkin_div);
+}
+
+/**
+ * get_csb_clk() - Read the CSB (Coheren System Bus) clock speed
+ * @im: Pointer to the MPC83xx main register map in question
+ *
+ * Return: The CSB clock speed value as a 32-bit number.
+ */
+static inline u32 get_csb_clk(immap_t *im)
+{
+	u8 spmf;
+
+	spmf = (get_spmr(im) & SPMR_SPMF) >> SPMR_SPMF_SHIFT;
+	return CONFIG_SYS_CLK_FREQ * spmf;
+}
+
+/**
+ * spmr_field() - Read a specific SPMR field
+ * @im:   Pointer to the MPC83xx main register map in question
+ * @mask: A bitmask that describes the bitfield to be read
+ *
+ * Return: The value of the bit field as a 32-bit number.
+ */
+static inline uint spmr_field(immap_t *im, u32 mask)
+{
+	/* Extract shift from bitmask */
+	uint shift = mask ? ffs(mask) - 1 : 0;
+
+	return (get_spmr(im) & mask) >> shift;
+}
+
+/**
+ * sccr_field() - Read a specific SCCR field
+ * @im:   Pointer to the MPC83xx main register map in question
+ * @mask: A bitmask that describes the bitfield to be read
+ *
+ * Return: The value of the bit field as a 32-bit number.
+ */
+static inline uint sccr_field(immap_t *im, u32 mask)
+{
+	/* Extract shift from bitmask */
+	uint shift = mask ? ffs(mask) - 1 : 0;
+
+	return (get_sccr(im) & mask) >> shift;
+}
+
+/**
+ * lcrr_field() - Read a specific LCRR field
+ * @im:   Pointer to the MPC83xx main register map in question
+ * @mask: A bitmask that describes the bitfield to be read
+ *
+ * Return: The value of the bit field as a 32-bit number.
+ */
+static inline uint lcrr_field(immap_t *im, u32 mask)
+{
+	/* Extract shift from bitmask */
+	uint shift = mask ? ffs(mask) - 1 : 0;
+
+	return (get_lcrr(im) & mask) >> shift;
+}