1 // SPDX-License-Identifier: GPL-2.0+
3 // Driver for Amlogic Meson SPI flash controller (SPIFC)
56 #define USER_UC_MASK		((BIT(5) - 1) << 27)
72  * @clk:	input clock of the built-in baud rate generator
90  * meson_spifc_wait_ready() - wait for the current operation to terminate
91  * @spifc:	the Meson SPI device
94 static int meson_spifc_wait_ready(struct meson_spifc *spifc)  in meson_spifc_wait_ready()  argument
100 		regmap_read(spifc->regmap, REG_SLAVE, &data);  in meson_spifc_wait_ready()
106 	return -ETIMEDOUT;  in meson_spifc_wait_ready()
110  * meson_spifc_drain_buffer() - copy data from device buffer to memory
111  * @spifc:	the Meson SPI device
115 static void meson_spifc_drain_buffer(struct meson_spifc *spifc, u8 *buf,  in meson_spifc_drain_buffer()  argument
122 		regmap_read(spifc->regmap, REG_C0 + i, &data);  in meson_spifc_drain_buffer()
124 		if (len - i >= 4) {  in meson_spifc_drain_buffer()
128 			memcpy(buf, &data, len - i);  in meson_spifc_drain_buffer()
136  * meson_spifc_fill_buffer() - copy data from memory to device buffer
137  * @spifc:	the Meson SPI device
141 static void meson_spifc_fill_buffer(struct meson_spifc *spifc, const u8 *buf,  in meson_spifc_fill_buffer()  argument
148 		if (len - i >= 4)  in meson_spifc_fill_buffer()
151 			memcpy(&data, buf, len - i);  in meson_spifc_fill_buffer()
153 		regmap_write(spifc->regmap, REG_C0 + i, data);  in meson_spifc_fill_buffer()
161  * meson_spifc_setup_speed() - program the clock divider
162  * @spifc:	the Meson SPI device
165 static void meson_spifc_setup_speed(struct meson_spifc *spifc, u32 speed)  in meson_spifc_setup_speed()  argument
170 	parent = clk_get_rate(spifc->clk);  in meson_spifc_setup_speed()
171 	n = max_t(int, parent / speed - 1, 1);  in meson_spifc_setup_speed()
173 	dev_dbg(spifc->dev, "parent %lu, speed %u, n %d\n", parent,  in meson_spifc_setup_speed()
178 	value |= (((n + 1) / 2 - 1) << CLOCK_CNT_HIGH_SHIFT) &  in meson_spifc_setup_speed()
181 	regmap_write(spifc->regmap, REG_CLOCK, value);  in meson_spifc_setup_speed()
185  * meson_spifc_txrx() - transfer a chunk of data
186  * @spifc:	the Meson SPI device
194 static int meson_spifc_txrx(struct meson_spifc *spifc,  in meson_spifc_txrx()  argument
202 	if (xfer->tx_buf)  in meson_spifc_txrx()
203 		meson_spifc_fill_buffer(spifc, xfer->tx_buf + offset, len);  in meson_spifc_txrx()
206 	regmap_update_bits(spifc->regmap, REG_USER, USER_UC_MASK,  in meson_spifc_txrx()
208 	regmap_write(spifc->regmap, REG_USER1,  in meson_spifc_txrx()
209 		     (8 * len - 1) << USER1_BN_UC_DOUT_SHIFT);  in meson_spifc_txrx()
212 	regmap_update_bits(spifc->regmap, REG_USER, USER_DIN_EN_MS,  in meson_spifc_txrx()
217 			keep_cs = xfer->cs_change;  in meson_spifc_txrx()
219 			keep_cs = !xfer->cs_change;  in meson_spifc_txrx()
222 	regmap_update_bits(spifc->regmap, REG_USER4, USER4_CS_ACT,  in meson_spifc_txrx()
226 	regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_TRST_DONE, 0);  in meson_spifc_txrx()
228 	regmap_update_bits(spifc->regmap, REG_CMD, CMD_USER, CMD_USER);  in meson_spifc_txrx()
230 	ret = meson_spifc_wait_ready(spifc);  in meson_spifc_txrx()
232 	if (!ret && xfer->rx_buf)  in meson_spifc_txrx()
233 		meson_spifc_drain_buffer(spifc, xfer->rx_buf + offset, len);  in meson_spifc_txrx()
239  * meson_spifc_transfer_one() - perform a single transfer
249 	struct meson_spifc *spifc = spi_master_get_devdata(master);  in meson_spifc_transfer_one()  local
252 	meson_spifc_setup_speed(spifc, xfer->speed_hz);  in meson_spifc_transfer_one()
254 	regmap_update_bits(spifc->regmap, REG_CTRL, CTRL_ENABLE_AHB, 0);  in meson_spifc_transfer_one()
256 	while (done < xfer->len && !ret) {  in meson_spifc_transfer_one()
257 		len = min_t(int, xfer->len - done, SPIFC_BUFFER_SIZE);  in meson_spifc_transfer_one()
258 		ret = meson_spifc_txrx(spifc, xfer, done, len,  in meson_spifc_transfer_one()
260 				       done + len >= xfer->len);  in meson_spifc_transfer_one()
264 	regmap_update_bits(spifc->regmap, REG_CTRL, CTRL_ENABLE_AHB,  in meson_spifc_transfer_one()
271  * meson_spifc_hw_init() - reset and initialize the SPI controller
272  * @spifc:	the Meson SPI device
274 static void meson_spifc_hw_init(struct meson_spifc *spifc)  in meson_spifc_hw_init()  argument
277 	regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_SW_RST,  in meson_spifc_hw_init()
280 	regmap_update_bits(spifc->regmap, REG_USER, USER_CMP_MODE, 0);  in meson_spifc_hw_init()
282 	regmap_update_bits(spifc->regmap, REG_SLAVE, SLAVE_OP_MODE, 0);  in meson_spifc_hw_init()
288 	struct meson_spifc *spifc;  in meson_spifc_probe()  local
293 	master = spi_alloc_master(&pdev->dev, sizeof(struct meson_spifc));  in meson_spifc_probe()
295 		return -ENOMEM;  in meson_spifc_probe()
299 	spifc = spi_master_get_devdata(master);  in meson_spifc_probe()
300 	spifc->dev = &pdev->dev;  in meson_spifc_probe()
308 	spifc->regmap = devm_regmap_init_mmio(spifc->dev, base,  in meson_spifc_probe()
310 	if (IS_ERR(spifc->regmap)) {  in meson_spifc_probe()
311 		ret = PTR_ERR(spifc->regmap);  in meson_spifc_probe()
315 	spifc->clk = devm_clk_get(spifc->dev, NULL);  in meson_spifc_probe()
316 	if (IS_ERR(spifc->clk)) {  in meson_spifc_probe()
317 		dev_err(spifc->dev, "missing clock\n");  in meson_spifc_probe()
318 		ret = PTR_ERR(spifc->clk);  in meson_spifc_probe()
322 	ret = clk_prepare_enable(spifc->clk);  in meson_spifc_probe()
324 		dev_err(spifc->dev, "can't prepare clock\n");  in meson_spifc_probe()
328 	rate = clk_get_rate(spifc->clk);  in meson_spifc_probe()
330 	master->num_chipselect = 1;  in meson_spifc_probe()
331 	master->dev.of_node = pdev->dev.of_node;  in meson_spifc_probe()
332 	master->bits_per_word_mask = SPI_BPW_MASK(8);  in meson_spifc_probe()
333 	master->auto_runtime_pm = true;  in meson_spifc_probe()
334 	master->transfer_one = meson_spifc_transfer_one;  in meson_spifc_probe()
335 	master->min_speed_hz = rate >> 6;  in meson_spifc_probe()
336 	master->max_speed_hz = rate >> 1;  in meson_spifc_probe()
338 	meson_spifc_hw_init(spifc);  in meson_spifc_probe()
340 	pm_runtime_set_active(spifc->dev);  in meson_spifc_probe()
341 	pm_runtime_enable(spifc->dev);  in meson_spifc_probe()
343 	ret = devm_spi_register_master(spifc->dev, master);  in meson_spifc_probe()
345 		dev_err(spifc->dev, "failed to register spi master\n");  in meson_spifc_probe()
351 	clk_disable_unprepare(spifc->clk);  in meson_spifc_probe()
352 	pm_runtime_disable(spifc->dev);  in meson_spifc_probe()
361 	struct meson_spifc *spifc = spi_master_get_devdata(master);  in meson_spifc_remove()  local
363 	pm_runtime_get_sync(&pdev->dev);  in meson_spifc_remove()
364 	clk_disable_unprepare(spifc->clk);  in meson_spifc_remove()
365 	pm_runtime_disable(&pdev->dev);  in meson_spifc_remove()
374 	struct meson_spifc *spifc = spi_master_get_devdata(master);  in meson_spifc_suspend()  local
382 		clk_disable_unprepare(spifc->clk);  in meson_spifc_suspend()
390 	struct meson_spifc *spifc = spi_master_get_devdata(master);  in meson_spifc_resume()  local
394 		ret = clk_prepare_enable(spifc->clk);  in meson_spifc_resume()
399 	meson_spifc_hw_init(spifc);  in meson_spifc_resume()
403 		clk_disable_unprepare(spifc->clk);  in meson_spifc_resume()
413 	struct meson_spifc *spifc = spi_master_get_devdata(master);  in meson_spifc_runtime_suspend()  local
415 	clk_disable_unprepare(spifc->clk);  in meson_spifc_runtime_suspend()
423 	struct meson_spifc *spifc = spi_master_get_devdata(master);  in meson_spifc_runtime_resume()  local
425 	return clk_prepare_enable(spifc->clk);  in meson_spifc_runtime_resume()
437 	{ .compatible = "amlogic,meson6-spifc", },
438 	{ .compatible = "amlogic,meson-gxbb-spifc", },
447 		.name		= "meson-spifc",
456 MODULE_DESCRIPTION("Amlogic Meson SPIFC driver");