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1/*2 * Driver for Amlogic Meson SPI communication controller (SPICC)3 *4 * Copyright (C) BayLibre, SAS5 * Author: Neil Armstrong <narmstrong@baylibre.com>6 *7 * SPDX-License-Identifier: GPL-2.0+8 */9 10#include <linux/bitfield.h>11#include <linux/clk.h>12#include <linux/clk-provider.h>13#include <linux/device.h>14#include <linux/io.h>15#include <linux/kernel.h>16#include <linux/module.h>17#include <linux/of.h>18#include <linux/platform_device.h>19#include <linux/spi/spi.h>20#include <linux/types.h>21#include <linux/interrupt.h>22#include <linux/reset.h>23#include <linux/pinctrl/consumer.h>24 25/*26 * The Meson SPICC controller could support DMA based transfers, but is not27 * implemented by the vendor code, and while having the registers documentation28 * it has never worked on the GXL Hardware.29 * The PIO mode is the only mode implemented, and due to badly designed HW :30 * - all transfers are cutted in 16 words burst because the FIFO hangs on31 *   TX underflow, and there is no TX "Half-Empty" interrupt, so we go by32 *   FIFO max size chunk only33 * - CS management is dumb, and goes UP between every burst, so is really a34 *   "Data Valid" signal than a Chip Select, GPIO link should be used instead35 *   to have a CS go down over the full transfer36 */37 38#define SPICC_MAX_BURST	12839 40/* Register Map */41#define SPICC_RXDATA	0x0042 43#define SPICC_TXDATA	0x0444 45#define SPICC_CONREG	0x0846#define SPICC_ENABLE		BIT(0)47#define SPICC_MODE_MASTER	BIT(1)48#define SPICC_XCH		BIT(2)49#define SPICC_SMC		BIT(3)50#define SPICC_POL		BIT(4)51#define SPICC_PHA		BIT(5)52#define SPICC_SSCTL		BIT(6)53#define SPICC_SSPOL		BIT(7)54#define SPICC_DRCTL_MASK	GENMASK(9, 8)55#define SPICC_DRCTL_IGNORE	056#define SPICC_DRCTL_FALLING	157#define SPICC_DRCTL_LOWLEVEL	258#define SPICC_CS_MASK		GENMASK(13, 12)59#define SPICC_DATARATE_MASK	GENMASK(18, 16)60#define SPICC_DATARATE_DIV4	061#define SPICC_DATARATE_DIV8	162#define SPICC_DATARATE_DIV16	263#define SPICC_DATARATE_DIV32	364#define SPICC_BITLENGTH_MASK	GENMASK(24, 19)65#define SPICC_BURSTLENGTH_MASK	GENMASK(31, 25)66 67#define SPICC_INTREG	0x0c68#define SPICC_TE_EN	BIT(0) /* TX FIFO Empty Interrupt */69#define SPICC_TH_EN	BIT(1) /* TX FIFO Half-Full Interrupt */70#define SPICC_TF_EN	BIT(2) /* TX FIFO Full Interrupt */71#define SPICC_RR_EN	BIT(3) /* RX FIFO Ready Interrupt */72#define SPICC_RH_EN	BIT(4) /* RX FIFO Half-Full Interrupt */73#define SPICC_RF_EN	BIT(5) /* RX FIFO Full Interrupt */74#define SPICC_RO_EN	BIT(6) /* RX FIFO Overflow Interrupt */75#define SPICC_TC_EN	BIT(7) /* Transfert Complete Interrupt */76 77#define SPICC_DMAREG	0x1078#define SPICC_DMA_ENABLE		BIT(0)79#define SPICC_TXFIFO_THRESHOLD_MASK	GENMASK(5, 1)80#define SPICC_RXFIFO_THRESHOLD_MASK	GENMASK(10, 6)81#define SPICC_READ_BURST_MASK		GENMASK(14, 11)82#define SPICC_WRITE_BURST_MASK		GENMASK(18, 15)83#define SPICC_DMA_URGENT		BIT(19)84#define SPICC_DMA_THREADID_MASK		GENMASK(25, 20)85#define SPICC_DMA_BURSTNUM_MASK		GENMASK(31, 26)86 87#define SPICC_STATREG	0x1488#define SPICC_TE	BIT(0) /* TX FIFO Empty Interrupt */89#define SPICC_TH	BIT(1) /* TX FIFO Half-Full Interrupt */90#define SPICC_TF	BIT(2) /* TX FIFO Full Interrupt */91#define SPICC_RR	BIT(3) /* RX FIFO Ready Interrupt */92#define SPICC_RH	BIT(4) /* RX FIFO Half-Full Interrupt */93#define SPICC_RF	BIT(5) /* RX FIFO Full Interrupt */94#define SPICC_RO	BIT(6) /* RX FIFO Overflow Interrupt */95#define SPICC_TC	BIT(7) /* Transfert Complete Interrupt */96 97#define SPICC_PERIODREG	0x1898#define SPICC_PERIOD	GENMASK(14, 0)	/* Wait cycles */99 100#define SPICC_TESTREG	0x1c101#define SPICC_TXCNT_MASK	GENMASK(4, 0)	/* TX FIFO Counter */102#define SPICC_RXCNT_MASK	GENMASK(9, 5)	/* RX FIFO Counter */103#define SPICC_SMSTATUS_MASK	GENMASK(12, 10)	/* State Machine Status */104#define SPICC_LBC_RO		BIT(13)	/* Loop Back Control Read-Only */105#define SPICC_LBC_W1		BIT(14) /* Loop Back Control Write-Only */106#define SPICC_SWAP_RO		BIT(14) /* RX FIFO Data Swap Read-Only */107#define SPICC_SWAP_W1		BIT(15) /* RX FIFO Data Swap Write-Only */108#define SPICC_DLYCTL_RO_MASK	GENMASK(20, 15) /* Delay Control Read-Only */109#define SPICC_MO_DELAY_MASK	GENMASK(17, 16) /* Master Output Delay */110#define SPICC_MO_NO_DELAY	0111#define SPICC_MO_DELAY_1_CYCLE	1112#define SPICC_MO_DELAY_2_CYCLE	2113#define SPICC_MO_DELAY_3_CYCLE	3114#define SPICC_MI_DELAY_MASK	GENMASK(19, 18) /* Master Input Delay */115#define SPICC_MI_NO_DELAY	0116#define SPICC_MI_DELAY_1_CYCLE	1117#define SPICC_MI_DELAY_2_CYCLE	2118#define SPICC_MI_DELAY_3_CYCLE	3119#define SPICC_MI_CAP_DELAY_MASK	GENMASK(21, 20) /* Master Capture Delay */120#define SPICC_CAP_AHEAD_2_CYCLE	0121#define SPICC_CAP_AHEAD_1_CYCLE	1122#define SPICC_CAP_NO_DELAY	2123#define SPICC_CAP_DELAY_1_CYCLE	3124#define SPICC_FIFORST_RO_MASK	GENMASK(22, 21) /* FIFO Softreset Read-Only */125#define SPICC_FIFORST_W1_MASK	GENMASK(23, 22) /* FIFO Softreset Write-Only */126 127#define SPICC_DRADDR	0x20	/* Read Address of DMA */128 129#define SPICC_DWADDR	0x24	/* Write Address of DMA */130 131#define SPICC_ENH_CTL0	0x38	/* Enhanced Feature */132#define SPICC_ENH_CLK_CS_DELAY_MASK	GENMASK(15, 0)133#define SPICC_ENH_DATARATE_MASK		GENMASK(23, 16)134#define SPICC_ENH_DATARATE_EN		BIT(24)135#define SPICC_ENH_MOSI_OEN		BIT(25)136#define SPICC_ENH_CLK_OEN		BIT(26)137#define SPICC_ENH_CS_OEN		BIT(27)138#define SPICC_ENH_CLK_CS_DELAY_EN	BIT(28)139#define SPICC_ENH_MAIN_CLK_AO		BIT(29)140 141#define writel_bits_relaxed(mask, val, addr) \142	writel_relaxed((readl_relaxed(addr) & ~(mask)) | (val), addr)143 144struct meson_spicc_data {145	unsigned int			max_speed_hz;146	unsigned int			min_speed_hz;147	unsigned int			fifo_size;148	bool				has_oen;149	bool				has_enhance_clk_div;150	bool				has_pclk;151};152 153struct meson_spicc_device {154	struct spi_controller		*host;155	struct platform_device		*pdev;156	void __iomem			*base;157	struct clk			*core;158	struct clk			*pclk;159	struct clk_divider		pow2_div;160	struct clk			*clk;161	struct spi_message		*message;162	struct spi_transfer		*xfer;163	struct completion		done;164	const struct meson_spicc_data	*data;165	u8				*tx_buf;166	u8				*rx_buf;167	unsigned int			bytes_per_word;168	unsigned long			tx_remain;169	unsigned long			rx_remain;170	unsigned long			xfer_remain;171	struct pinctrl			*pinctrl;172	struct pinctrl_state		*pins_idle_high;173	struct pinctrl_state		*pins_idle_low;174};175 176#define pow2_clk_to_spicc(_div) container_of(_div, struct meson_spicc_device, pow2_div)177 178static void meson_spicc_oen_enable(struct meson_spicc_device *spicc)179{180	u32 conf;181 182	if (!spicc->data->has_oen) {183		/* Try to get pinctrl states for idle high/low */184		spicc->pins_idle_high = pinctrl_lookup_state(spicc->pinctrl,185							     "idle-high");186		if (IS_ERR(spicc->pins_idle_high)) {187			dev_warn(&spicc->pdev->dev, "can't get idle-high pinctrl\n");188			spicc->pins_idle_high = NULL;189		}190		spicc->pins_idle_low = pinctrl_lookup_state(spicc->pinctrl,191							     "idle-low");192		if (IS_ERR(spicc->pins_idle_low)) {193			dev_warn(&spicc->pdev->dev, "can't get idle-low pinctrl\n");194			spicc->pins_idle_low = NULL;195		}196		return;197	}198 199	conf = readl_relaxed(spicc->base + SPICC_ENH_CTL0) |200		SPICC_ENH_MOSI_OEN | SPICC_ENH_CLK_OEN | SPICC_ENH_CS_OEN;201 202	writel_relaxed(conf, spicc->base + SPICC_ENH_CTL0);203}204 205static inline bool meson_spicc_txfull(struct meson_spicc_device *spicc)206{207	return !!FIELD_GET(SPICC_TF,208			   readl_relaxed(spicc->base + SPICC_STATREG));209}210 211static inline bool meson_spicc_rxready(struct meson_spicc_device *spicc)212{213	return FIELD_GET(SPICC_RH | SPICC_RR | SPICC_RF,214			 readl_relaxed(spicc->base + SPICC_STATREG));215}216 217static inline u32 meson_spicc_pull_data(struct meson_spicc_device *spicc)218{219	unsigned int bytes = spicc->bytes_per_word;220	unsigned int byte_shift = 0;221	u32 data = 0;222	u8 byte;223 224	while (bytes--) {225		byte = *spicc->tx_buf++;226		data |= (byte & 0xff) << byte_shift;227		byte_shift += 8;228	}229 230	spicc->tx_remain--;231	return data;232}233 234static inline void meson_spicc_push_data(struct meson_spicc_device *spicc,235					 u32 data)236{237	unsigned int bytes = spicc->bytes_per_word;238	unsigned int byte_shift = 0;239	u8 byte;240 241	while (bytes--) {242		byte = (data >> byte_shift) & 0xff;243		*spicc->rx_buf++ = byte;244		byte_shift += 8;245	}246 247	spicc->rx_remain--;248}249 250static inline void meson_spicc_rx(struct meson_spicc_device *spicc)251{252	/* Empty RX FIFO */253	while (spicc->rx_remain &&254	       meson_spicc_rxready(spicc))255		meson_spicc_push_data(spicc,256				readl_relaxed(spicc->base + SPICC_RXDATA));257}258 259static inline void meson_spicc_tx(struct meson_spicc_device *spicc)260{261	/* Fill Up TX FIFO */262	while (spicc->tx_remain &&263	       !meson_spicc_txfull(spicc))264		writel_relaxed(meson_spicc_pull_data(spicc),265			       spicc->base + SPICC_TXDATA);266}267 268static inline void meson_spicc_setup_burst(struct meson_spicc_device *spicc)269{270 271	unsigned int burst_len = min_t(unsigned int,272				       spicc->xfer_remain /273				       spicc->bytes_per_word,274				       spicc->data->fifo_size);275	/* Setup Xfer variables */276	spicc->tx_remain = burst_len;277	spicc->rx_remain = burst_len;278	spicc->xfer_remain -= burst_len * spicc->bytes_per_word;279 280	/* Setup burst length */281	writel_bits_relaxed(SPICC_BURSTLENGTH_MASK,282			FIELD_PREP(SPICC_BURSTLENGTH_MASK,283				burst_len - 1),284			spicc->base + SPICC_CONREG);285 286	/* Fill TX FIFO */287	meson_spicc_tx(spicc);288}289 290static irqreturn_t meson_spicc_irq(int irq, void *data)291{292	struct meson_spicc_device *spicc = (void *) data;293 294	writel_bits_relaxed(SPICC_TC, SPICC_TC, spicc->base + SPICC_STATREG);295 296	/* Empty RX FIFO */297	meson_spicc_rx(spicc);298 299	if (!spicc->xfer_remain) {300		/* Disable all IRQs */301		writel(0, spicc->base + SPICC_INTREG);302 303		complete(&spicc->done);304 305		return IRQ_HANDLED;306	}307 308	/* Setup burst */309	meson_spicc_setup_burst(spicc);310 311	/* Start burst */312	writel_bits_relaxed(SPICC_XCH, SPICC_XCH, spicc->base + SPICC_CONREG);313 314	return IRQ_HANDLED;315}316 317static void meson_spicc_auto_io_delay(struct meson_spicc_device *spicc)318{319	u32 div, hz;320	u32 mi_delay, cap_delay;321	u32 conf;322 323	if (spicc->data->has_enhance_clk_div) {324		div = FIELD_GET(SPICC_ENH_DATARATE_MASK,325				readl_relaxed(spicc->base + SPICC_ENH_CTL0));326		div++;327		div <<= 1;328	} else {329		div = FIELD_GET(SPICC_DATARATE_MASK,330				readl_relaxed(spicc->base + SPICC_CONREG));331		div += 2;332		div = 1 << div;333	}334 335	mi_delay = SPICC_MI_NO_DELAY;336	cap_delay = SPICC_CAP_AHEAD_2_CYCLE;337	hz = clk_get_rate(spicc->clk);338 339	if (hz >= 100000000)340		cap_delay = SPICC_CAP_DELAY_1_CYCLE;341	else if (hz >= 80000000)342		cap_delay = SPICC_CAP_NO_DELAY;343	else if (hz >= 40000000)344		cap_delay = SPICC_CAP_AHEAD_1_CYCLE;345	else if (div >= 16)346		mi_delay = SPICC_MI_DELAY_3_CYCLE;347	else if (div >= 8)348		mi_delay = SPICC_MI_DELAY_2_CYCLE;349	else if (div >= 6)350		mi_delay = SPICC_MI_DELAY_1_CYCLE;351 352	conf = readl_relaxed(spicc->base + SPICC_TESTREG);353	conf &= ~(SPICC_MO_DELAY_MASK | SPICC_MI_DELAY_MASK354		  | SPICC_MI_CAP_DELAY_MASK);355	conf |= FIELD_PREP(SPICC_MI_DELAY_MASK, mi_delay);356	conf |= FIELD_PREP(SPICC_MI_CAP_DELAY_MASK, cap_delay);357	writel_relaxed(conf, spicc->base + SPICC_TESTREG);358}359 360static void meson_spicc_setup_xfer(struct meson_spicc_device *spicc,361				   struct spi_transfer *xfer)362{363	u32 conf, conf_orig;364 365	/* Read original configuration */366	conf = conf_orig = readl_relaxed(spicc->base + SPICC_CONREG);367 368	/* Setup word width */369	conf &= ~SPICC_BITLENGTH_MASK;370	conf |= FIELD_PREP(SPICC_BITLENGTH_MASK,371			   (spicc->bytes_per_word << 3) - 1);372 373	/* Ignore if unchanged */374	if (conf != conf_orig)375		writel_relaxed(conf, spicc->base + SPICC_CONREG);376 377	clk_set_rate(spicc->clk, xfer->speed_hz);378 379	meson_spicc_auto_io_delay(spicc);380 381	writel_relaxed(0, spicc->base + SPICC_DMAREG);382}383 384static void meson_spicc_reset_fifo(struct meson_spicc_device *spicc)385{386	if (spicc->data->has_oen)387		writel_bits_relaxed(SPICC_ENH_MAIN_CLK_AO,388				    SPICC_ENH_MAIN_CLK_AO,389				    spicc->base + SPICC_ENH_CTL0);390 391	writel_bits_relaxed(SPICC_FIFORST_W1_MASK, SPICC_FIFORST_W1_MASK,392			    spicc->base + SPICC_TESTREG);393 394	while (meson_spicc_rxready(spicc))395		readl_relaxed(spicc->base + SPICC_RXDATA);396 397	if (spicc->data->has_oen)398		writel_bits_relaxed(SPICC_ENH_MAIN_CLK_AO, 0,399				    spicc->base + SPICC_ENH_CTL0);400}401 402static int meson_spicc_transfer_one(struct spi_controller *host,403				    struct spi_device *spi,404				    struct spi_transfer *xfer)405{406	struct meson_spicc_device *spicc = spi_controller_get_devdata(host);407	uint64_t timeout;408 409	/* Store current transfer */410	spicc->xfer = xfer;411 412	/* Setup transfer parameters */413	spicc->tx_buf = (u8 *)xfer->tx_buf;414	spicc->rx_buf = (u8 *)xfer->rx_buf;415	spicc->xfer_remain = xfer->len;416 417	/* Pre-calculate word size */418	spicc->bytes_per_word =419	   DIV_ROUND_UP(spicc->xfer->bits_per_word, 8);420 421	if (xfer->len % spicc->bytes_per_word)422		return -EINVAL;423 424	/* Setup transfer parameters */425	meson_spicc_setup_xfer(spicc, xfer);426 427	meson_spicc_reset_fifo(spicc);428 429	/* Setup burst */430	meson_spicc_setup_burst(spicc);431 432	/* Setup wait for completion */433	reinit_completion(&spicc->done);434 435	/* For each byte we wait for 8 cycles of the SPI clock */436	timeout = 8LL * MSEC_PER_SEC * xfer->len;437	do_div(timeout, xfer->speed_hz);438 439	/* Add 10us delay between each fifo bursts */440	timeout += ((xfer->len >> 4) * 10) / MSEC_PER_SEC;441 442	/* Increase it twice and add 200 ms tolerance */443	timeout += timeout + 200;444 445	/* Start burst */446	writel_bits_relaxed(SPICC_XCH, SPICC_XCH, spicc->base + SPICC_CONREG);447 448	/* Enable interrupts */449	writel_relaxed(SPICC_TC_EN, spicc->base + SPICC_INTREG);450 451	if (!wait_for_completion_timeout(&spicc->done, msecs_to_jiffies(timeout)))452		return -ETIMEDOUT;453 454	return 0;455}456 457static int meson_spicc_prepare_message(struct spi_controller *host,458				       struct spi_message *message)459{460	struct meson_spicc_device *spicc = spi_controller_get_devdata(host);461	struct spi_device *spi = message->spi;462	u32 conf = readl_relaxed(spicc->base + SPICC_CONREG) & SPICC_DATARATE_MASK;463 464	/* Store current message */465	spicc->message = message;466 467	/* Enable Master */468	conf |= SPICC_ENABLE;469	conf |= SPICC_MODE_MASTER;470 471	/* SMC = 0 */472 473	/* Setup transfer mode */474	if (spi->mode & SPI_CPOL)475		conf |= SPICC_POL;476	else477		conf &= ~SPICC_POL;478 479	if (!spicc->data->has_oen) {480		if (spi->mode & SPI_CPOL) {481			if (spicc->pins_idle_high)482				pinctrl_select_state(spicc->pinctrl, spicc->pins_idle_high);483		} else {484			if (spicc->pins_idle_low)485				pinctrl_select_state(spicc->pinctrl, spicc->pins_idle_low);486		}487	}488 489	if (spi->mode & SPI_CPHA)490		conf |= SPICC_PHA;491	else492		conf &= ~SPICC_PHA;493 494	/* SSCTL = 0 */495 496	if (spi->mode & SPI_CS_HIGH)497		conf |= SPICC_SSPOL;498	else499		conf &= ~SPICC_SSPOL;500 501	if (spi->mode & SPI_READY)502		conf |= FIELD_PREP(SPICC_DRCTL_MASK, SPICC_DRCTL_LOWLEVEL);503	else504		conf |= FIELD_PREP(SPICC_DRCTL_MASK, SPICC_DRCTL_IGNORE);505 506	/* Select CS */507	conf |= FIELD_PREP(SPICC_CS_MASK, spi_get_chipselect(spi, 0));508 509	/* Default 8bit word */510	conf |= FIELD_PREP(SPICC_BITLENGTH_MASK, 8 - 1);511 512	writel_relaxed(conf, spicc->base + SPICC_CONREG);513 514	/* Setup no wait cycles by default */515	writel_relaxed(0, spicc->base + SPICC_PERIODREG);516 517	writel_bits_relaxed(SPICC_LBC_W1,518			    spi->mode & SPI_LOOP ? SPICC_LBC_W1 : 0,519			    spicc->base + SPICC_TESTREG);520 521	return 0;522}523 524static int meson_spicc_unprepare_transfer(struct spi_controller *host)525{526	struct meson_spicc_device *spicc = spi_controller_get_devdata(host);527	u32 conf = readl_relaxed(spicc->base + SPICC_CONREG) & SPICC_DATARATE_MASK;528 529	/* Disable all IRQs */530	writel(0, spicc->base + SPICC_INTREG);531 532	device_reset_optional(&spicc->pdev->dev);533 534	/* Set default configuration, keeping datarate field */535	writel_relaxed(conf, spicc->base + SPICC_CONREG);536 537	if (!spicc->data->has_oen)538		pinctrl_select_default_state(&spicc->pdev->dev);539 540	return 0;541}542 543static int meson_spicc_setup(struct spi_device *spi)544{545	if (!spi->controller_state)546		spi->controller_state = spi_controller_get_devdata(spi->controller);547 548	return 0;549}550 551static void meson_spicc_cleanup(struct spi_device *spi)552{553	spi->controller_state = NULL;554}555 556/*557 * The Clock Mux558 *            x-----------------x   x------------x    x------\559 *        |---| pow2 fixed div  |---| pow2 div   |----|      |560 *        |   x-----------------x   x------------x    |      |561 * src ---|                                           | mux  |-- out562 *        |   x-----------------x   x------------x    |      |563 *        |---| enh fixed div   |---| enh div    |0---|      |564 *            x-----------------x   x------------x    x------/565 *566 * Clk path for GX series:567 *    src -> pow2 fixed div -> pow2 div -> out568 *569 * Clk path for AXG series:570 *    src -> pow2 fixed div -> pow2 div -> mux -> out571 *    src -> enh fixed div -> enh div -> mux -> out572 *573 * Clk path for G12A series:574 *    pclk -> pow2 fixed div -> pow2 div -> mux -> out575 *    pclk -> enh fixed div -> enh div -> mux -> out576 *577 * The pow2 divider is tied to the controller HW state, and the578 * divider is only valid when the controller is initialized.579 *580 * A set of clock ops is added to make sure we don't read/set this581 * clock rate while the controller is in an unknown state.582 */583 584static unsigned long meson_spicc_pow2_recalc_rate(struct clk_hw *hw,585						  unsigned long parent_rate)586{587	struct clk_divider *divider = to_clk_divider(hw);588	struct meson_spicc_device *spicc = pow2_clk_to_spicc(divider);589 590	if (!spicc->host->cur_msg)591		return 0;592 593	return clk_divider_ops.recalc_rate(hw, parent_rate);594}595 596static int meson_spicc_pow2_determine_rate(struct clk_hw *hw,597					   struct clk_rate_request *req)598{599	struct clk_divider *divider = to_clk_divider(hw);600	struct meson_spicc_device *spicc = pow2_clk_to_spicc(divider);601 602	if (!spicc->host->cur_msg)603		return -EINVAL;604 605	return clk_divider_ops.determine_rate(hw, req);606}607 608static int meson_spicc_pow2_set_rate(struct clk_hw *hw, unsigned long rate,609				     unsigned long parent_rate)610{611	struct clk_divider *divider = to_clk_divider(hw);612	struct meson_spicc_device *spicc = pow2_clk_to_spicc(divider);613 614	if (!spicc->host->cur_msg)615		return -EINVAL;616 617	return clk_divider_ops.set_rate(hw, rate, parent_rate);618}619 620static const struct clk_ops meson_spicc_pow2_clk_ops = {621	.recalc_rate = meson_spicc_pow2_recalc_rate,622	.determine_rate = meson_spicc_pow2_determine_rate,623	.set_rate = meson_spicc_pow2_set_rate,624};625 626static int meson_spicc_pow2_clk_init(struct meson_spicc_device *spicc)627{628	struct device *dev = &spicc->pdev->dev;629	struct clk_fixed_factor *pow2_fixed_div;630	struct clk_init_data init;631	struct clk *clk;632	struct clk_parent_data parent_data[2];633	char name[64];634 635	memset(&init, 0, sizeof(init));636	memset(&parent_data, 0, sizeof(parent_data));637 638	init.parent_data = parent_data;639 640	/* algorithm for pow2 div: rate = freq / 4 / (2 ^ N) */641 642	pow2_fixed_div = devm_kzalloc(dev, sizeof(*pow2_fixed_div), GFP_KERNEL);643	if (!pow2_fixed_div)644		return -ENOMEM;645 646	snprintf(name, sizeof(name), "%s#pow2_fixed_div", dev_name(dev));647	init.name = name;648	init.ops = &clk_fixed_factor_ops;649	if (spicc->data->has_pclk) {650		init.flags = CLK_SET_RATE_PARENT;651		parent_data[0].hw = __clk_get_hw(spicc->pclk);652	} else {653		init.flags = 0;654		parent_data[0].hw = __clk_get_hw(spicc->core);655	}656	init.num_parents = 1;657 658	pow2_fixed_div->mult = 1;659	pow2_fixed_div->div = 4;660	pow2_fixed_div->hw.init = &init;661 662	clk = devm_clk_register(dev, &pow2_fixed_div->hw);663	if (WARN_ON(IS_ERR(clk)))664		return PTR_ERR(clk);665 666	snprintf(name, sizeof(name), "%s#pow2_div", dev_name(dev));667	init.name = name;668	init.ops = &meson_spicc_pow2_clk_ops;669	/*670	 * Set NOCACHE here to make sure we read the actual HW value671	 * since we reset the HW after each transfer.672	 */673	init.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;674	parent_data[0].hw = &pow2_fixed_div->hw;675	init.num_parents = 1;676 677	spicc->pow2_div.shift = 16;678	spicc->pow2_div.width = 3;679	spicc->pow2_div.flags = CLK_DIVIDER_POWER_OF_TWO;680	spicc->pow2_div.reg = spicc->base + SPICC_CONREG;681	spicc->pow2_div.hw.init = &init;682 683	spicc->clk = devm_clk_register(dev, &spicc->pow2_div.hw);684	if (WARN_ON(IS_ERR(spicc->clk)))685		return PTR_ERR(spicc->clk);686 687	return 0;688}689 690static int meson_spicc_enh_clk_init(struct meson_spicc_device *spicc)691{692	struct device *dev = &spicc->pdev->dev;693	struct clk_fixed_factor *enh_fixed_div;694	struct clk_divider *enh_div;695	struct clk_mux *mux;696	struct clk_init_data init;697	struct clk *clk;698	struct clk_parent_data parent_data[2];699	char name[64];700 701	memset(&init, 0, sizeof(init));702	memset(&parent_data, 0, sizeof(parent_data));703 704	init.parent_data = parent_data;705 706	/* algorithm for enh div: rate = freq / 2 / (N + 1) */707 708	enh_fixed_div = devm_kzalloc(dev, sizeof(*enh_fixed_div), GFP_KERNEL);709	if (!enh_fixed_div)710		return -ENOMEM;711 712	snprintf(name, sizeof(name), "%s#enh_fixed_div", dev_name(dev));713	init.name = name;714	init.ops = &clk_fixed_factor_ops;715	if (spicc->data->has_pclk) {716		init.flags = CLK_SET_RATE_PARENT;717		parent_data[0].hw = __clk_get_hw(spicc->pclk);718	} else {719		init.flags = 0;720		parent_data[0].hw = __clk_get_hw(spicc->core);721	}722	init.num_parents = 1;723 724	enh_fixed_div->mult = 1;725	enh_fixed_div->div = 2;726	enh_fixed_div->hw.init = &init;727 728	clk = devm_clk_register(dev, &enh_fixed_div->hw);729	if (WARN_ON(IS_ERR(clk)))730		return PTR_ERR(clk);731 732	enh_div = devm_kzalloc(dev, sizeof(*enh_div), GFP_KERNEL);733	if (!enh_div)734		return -ENOMEM;735 736	snprintf(name, sizeof(name), "%s#enh_div", dev_name(dev));737	init.name = name;738	init.ops = &clk_divider_ops;739	init.flags = CLK_SET_RATE_PARENT;740	parent_data[0].hw = &enh_fixed_div->hw;741	init.num_parents = 1;742 743	enh_div->shift	= 16;744	enh_div->width	= 8;745	enh_div->reg = spicc->base + SPICC_ENH_CTL0;746	enh_div->hw.init = &init;747 748	clk = devm_clk_register(dev, &enh_div->hw);749	if (WARN_ON(IS_ERR(clk)))750		return PTR_ERR(clk);751 752	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);753	if (!mux)754		return -ENOMEM;755 756	snprintf(name, sizeof(name), "%s#sel", dev_name(dev));757	init.name = name;758	init.ops = &clk_mux_ops;759	parent_data[0].hw = &spicc->pow2_div.hw;760	parent_data[1].hw = &enh_div->hw;761	init.num_parents = 2;762	init.flags = CLK_SET_RATE_PARENT;763 764	mux->mask = 0x1;765	mux->shift = 24;766	mux->reg = spicc->base + SPICC_ENH_CTL0;767	mux->hw.init = &init;768 769	spicc->clk = devm_clk_register(dev, &mux->hw);770	if (WARN_ON(IS_ERR(spicc->clk)))771		return PTR_ERR(spicc->clk);772 773	return 0;774}775 776static int meson_spicc_probe(struct platform_device *pdev)777{778	struct spi_controller *host;779	struct meson_spicc_device *spicc;780	int ret, irq;781 782	host = spi_alloc_host(&pdev->dev, sizeof(*spicc));783	if (!host) {784		dev_err(&pdev->dev, "host allocation failed\n");785		return -ENOMEM;786	}787	spicc = spi_controller_get_devdata(host);788	spicc->host = host;789 790	spicc->data = of_device_get_match_data(&pdev->dev);791	if (!spicc->data) {792		dev_err(&pdev->dev, "failed to get match data\n");793		ret = -EINVAL;794		goto out_host;795	}796 797	spicc->pdev = pdev;798	platform_set_drvdata(pdev, spicc);799 800	init_completion(&spicc->done);801 802	spicc->base = devm_platform_ioremap_resource(pdev, 0);803	if (IS_ERR(spicc->base)) {804		dev_err(&pdev->dev, "io resource mapping failed\n");805		ret = PTR_ERR(spicc->base);806		goto out_host;807	}808 809	/* Set master mode and enable controller */810	writel_relaxed(SPICC_ENABLE | SPICC_MODE_MASTER,811		       spicc->base + SPICC_CONREG);812 813	/* Disable all IRQs */814	writel_relaxed(0, spicc->base + SPICC_INTREG);815 816	irq = platform_get_irq(pdev, 0);817	if (irq < 0) {818		ret = irq;819		goto out_host;820	}821 822	ret = devm_request_irq(&pdev->dev, irq, meson_spicc_irq,823			       0, NULL, spicc);824	if (ret) {825		dev_err(&pdev->dev, "irq request failed\n");826		goto out_host;827	}828 829	spicc->core = devm_clk_get_enabled(&pdev->dev, "core");830	if (IS_ERR(spicc->core)) {831		dev_err(&pdev->dev, "core clock request failed\n");832		ret = PTR_ERR(spicc->core);833		goto out_host;834	}835 836	if (spicc->data->has_pclk) {837		spicc->pclk = devm_clk_get_enabled(&pdev->dev, "pclk");838		if (IS_ERR(spicc->pclk)) {839			dev_err(&pdev->dev, "pclk clock request failed\n");840			ret = PTR_ERR(spicc->pclk);841			goto out_host;842		}843	}844 845	spicc->pinctrl = devm_pinctrl_get(&pdev->dev);846	if (IS_ERR(spicc->pinctrl)) {847		ret = PTR_ERR(spicc->pinctrl);848		goto out_host;849	}850 851	device_reset_optional(&pdev->dev);852 853	host->num_chipselect = 4;854	host->dev.of_node = pdev->dev.of_node;855	host->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LOOP;856	host->bits_per_word_mask = SPI_BPW_MASK(32) |857				   SPI_BPW_MASK(24) |858				   SPI_BPW_MASK(16) |859				   SPI_BPW_MASK(8);860	host->flags = (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX);861	host->min_speed_hz = spicc->data->min_speed_hz;862	host->max_speed_hz = spicc->data->max_speed_hz;863	host->setup = meson_spicc_setup;864	host->cleanup = meson_spicc_cleanup;865	host->prepare_message = meson_spicc_prepare_message;866	host->unprepare_transfer_hardware = meson_spicc_unprepare_transfer;867	host->transfer_one = meson_spicc_transfer_one;868	host->use_gpio_descriptors = true;869 870	meson_spicc_oen_enable(spicc);871 872	ret = meson_spicc_pow2_clk_init(spicc);873	if (ret) {874		dev_err(&pdev->dev, "pow2 clock registration failed\n");875		goto out_host;876	}877 878	if (spicc->data->has_enhance_clk_div) {879		ret = meson_spicc_enh_clk_init(spicc);880		if (ret) {881			dev_err(&pdev->dev, "clock registration failed\n");882			goto out_host;883		}884	}885 886	ret = devm_spi_register_controller(&pdev->dev, host);887	if (ret) {888		dev_err(&pdev->dev, "spi registration failed\n");889		goto out_host;890	}891 892	return 0;893 894out_host:895	spi_controller_put(host);896 897	return ret;898}899 900static void meson_spicc_remove(struct platform_device *pdev)901{902	struct meson_spicc_device *spicc = platform_get_drvdata(pdev);903 904	/* Disable SPI */905	writel(0, spicc->base + SPICC_CONREG);906 907	spi_controller_put(spicc->host);908}909 910static const struct meson_spicc_data meson_spicc_gx_data = {911	.max_speed_hz		= 30000000,912	.min_speed_hz		= 325000,913	.fifo_size		= 16,914};915 916static const struct meson_spicc_data meson_spicc_axg_data = {917	.max_speed_hz		= 80000000,918	.min_speed_hz		= 325000,919	.fifo_size		= 16,920	.has_oen		= true,921	.has_enhance_clk_div	= true,922};923 924static const struct meson_spicc_data meson_spicc_g12a_data = {925	.max_speed_hz		= 166666666,926	.min_speed_hz		= 50000,927	.fifo_size		= 15,928	.has_oen		= true,929	.has_enhance_clk_div	= true,930	.has_pclk		= true,931};932 933static const struct of_device_id meson_spicc_of_match[] = {934	{935		.compatible	= "amlogic,meson-gx-spicc",936		.data		= &meson_spicc_gx_data,937	},938	{939		.compatible = "amlogic,meson-axg-spicc",940		.data		= &meson_spicc_axg_data,941	},942	{943		.compatible = "amlogic,meson-g12a-spicc",944		.data		= &meson_spicc_g12a_data,945	},946	{ /* sentinel */ }947};948MODULE_DEVICE_TABLE(of, meson_spicc_of_match);949 950static struct platform_driver meson_spicc_driver = {951	.probe   = meson_spicc_probe,952	.remove_new = meson_spicc_remove,953	.driver  = {954		.name = "meson-spicc",955		.of_match_table = of_match_ptr(meson_spicc_of_match),956	},957};958 959module_platform_driver(meson_spicc_driver);960 961MODULE_DESCRIPTION("Meson SPI Communication Controller driver");962MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");963MODULE_LICENSE("GPL");964