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1// SPDX-License-Identifier: GPL-2.02/*3 * LiteX LiteSDCard driver4 *5 * Copyright (C) 2019-2020 Antmicro <contact@antmicro.com>6 * Copyright (C) 2019-2020 Kamil Rakoczy <krakoczy@antmicro.com>7 * Copyright (C) 2019-2020 Maciej Dudek <mdudek@internships.antmicro.com>8 * Copyright (C) 2020 Paul Mackerras <paulus@ozlabs.org>9 * Copyright (C) 2020-2022 Gabriel Somlo <gsomlo@gmail.com>10 */11 12#include <linux/bits.h>13#include <linux/clk.h>14#include <linux/delay.h>15#include <linux/dma-mapping.h>16#include <linux/interrupt.h>17#include <linux/iopoll.h>18#include <linux/litex.h>19#include <linux/mod_devicetable.h>20#include <linux/module.h>21#include <linux/platform_device.h>22 23#include <linux/mmc/host.h>24#include <linux/mmc/mmc.h>25#include <linux/mmc/sd.h>26 27#define LITEX_PHY_CARDDETECT  0x0028#define LITEX_PHY_CLOCKERDIV  0x0429#define LITEX_PHY_INITIALIZE  0x0830#define LITEX_PHY_WRITESTATUS 0x0C31#define LITEX_CORE_CMDARG     0x0032#define LITEX_CORE_CMDCMD     0x0433#define LITEX_CORE_CMDSND     0x0834#define LITEX_CORE_CMDRSP     0x0C35#define LITEX_CORE_CMDEVT     0x1C36#define LITEX_CORE_DATEVT     0x2037#define LITEX_CORE_BLKLEN     0x2438#define LITEX_CORE_BLKCNT     0x2839#define LITEX_BLK2MEM_BASE    0x0040#define LITEX_BLK2MEM_LEN     0x0841#define LITEX_BLK2MEM_ENA     0x0C42#define LITEX_BLK2MEM_DONE    0x1043#define LITEX_BLK2MEM_LOOP    0x1444#define LITEX_MEM2BLK_BASE    0x0045#define LITEX_MEM2BLK_LEN     0x0846#define LITEX_MEM2BLK_ENA     0x0C47#define LITEX_MEM2BLK_DONE    0x1048#define LITEX_MEM2BLK_LOOP    0x1449#define LITEX_MEM2BLK         0x1850#define LITEX_IRQ_STATUS      0x0051#define LITEX_IRQ_PENDING     0x0452#define LITEX_IRQ_ENABLE      0x0853 54#define SD_CTL_DATA_XFER_NONE  055#define SD_CTL_DATA_XFER_READ  156#define SD_CTL_DATA_XFER_WRITE 257 58#define SD_CTL_RESP_NONE       059#define SD_CTL_RESP_SHORT      160#define SD_CTL_RESP_LONG       261#define SD_CTL_RESP_SHORT_BUSY 362 63#define SD_BIT_DONE    BIT(0)64#define SD_BIT_WR_ERR  BIT(1)65#define SD_BIT_TIMEOUT BIT(2)66#define SD_BIT_CRC_ERR BIT(3)67 68#define SD_SLEEP_US       569#define SD_TIMEOUT_US 2000070 71#define SDIRQ_CARD_DETECT    172#define SDIRQ_SD_TO_MEM_DONE 273#define SDIRQ_MEM_TO_SD_DONE 474#define SDIRQ_CMD_DONE       875 76struct litex_mmc_host {77	struct mmc_host *mmc;78 79	void __iomem *sdphy;80	void __iomem *sdcore;81	void __iomem *sdreader;82	void __iomem *sdwriter;83	void __iomem *sdirq;84 85	void *buffer;86	size_t buf_size;87	dma_addr_t dma;88 89	struct completion cmd_done;90	int irq;91 92	unsigned int ref_clk;93	unsigned int sd_clk;94 95	u32 resp[4];96	u16 rca;97 98	bool is_bus_width_set;99	bool app_cmd;100};101 102static int litex_mmc_sdcard_wait_done(void __iomem *reg, struct device *dev)103{104	u8 evt;105	int ret;106 107	ret = readx_poll_timeout(litex_read8, reg, evt, evt & SD_BIT_DONE,108				 SD_SLEEP_US, SD_TIMEOUT_US);109	if (ret)110		return ret;111	if (evt == SD_BIT_DONE)112		return 0;113	if (evt & SD_BIT_WR_ERR)114		return -EIO;115	if (evt & SD_BIT_TIMEOUT)116		return -ETIMEDOUT;117	if (evt & SD_BIT_CRC_ERR)118		return -EILSEQ;119	dev_err(dev, "%s: unknown error (evt=%x)\n", __func__, evt);120	return -EINVAL;121}122 123static int litex_mmc_send_cmd(struct litex_mmc_host *host,124			      u8 cmd, u32 arg, u8 response_len, u8 transfer)125{126	struct device *dev = mmc_dev(host->mmc);127	void __iomem *reg;128	int ret;129	u8 evt;130 131	litex_write32(host->sdcore + LITEX_CORE_CMDARG, arg);132	litex_write32(host->sdcore + LITEX_CORE_CMDCMD,133		      cmd << 8 | transfer << 5 | response_len);134	litex_write8(host->sdcore + LITEX_CORE_CMDSND, 1);135 136	/*137	 * Wait for an interrupt if we have an interrupt and either there is138	 * data to be transferred, or if the card can report busy via DAT0.139	 */140	if (host->irq > 0 &&141	    (transfer != SD_CTL_DATA_XFER_NONE ||142	     response_len == SD_CTL_RESP_SHORT_BUSY)) {143		reinit_completion(&host->cmd_done);144		litex_write32(host->sdirq + LITEX_IRQ_ENABLE,145			      SDIRQ_CMD_DONE | SDIRQ_CARD_DETECT);146		wait_for_completion(&host->cmd_done);147	}148 149	ret = litex_mmc_sdcard_wait_done(host->sdcore + LITEX_CORE_CMDEVT, dev);150	if (ret) {151		dev_err(dev, "Command (cmd %d) error, status %d\n", cmd, ret);152		return ret;153	}154 155	if (response_len != SD_CTL_RESP_NONE) {156		/*157		 * NOTE: this matches the semantics of litex_read32()158		 * regardless of underlying arch endianness!159		 */160		memcpy_fromio(host->resp,161			      host->sdcore + LITEX_CORE_CMDRSP, 0x10);162	}163 164	if (!host->app_cmd && cmd == SD_SEND_RELATIVE_ADDR)165		host->rca = (host->resp[3] >> 16);166 167	host->app_cmd = (cmd == MMC_APP_CMD);168 169	if (transfer == SD_CTL_DATA_XFER_NONE)170		return ret; /* OK from prior litex_mmc_sdcard_wait_done() */171 172	ret = litex_mmc_sdcard_wait_done(host->sdcore + LITEX_CORE_DATEVT, dev);173	if (ret) {174		dev_err(dev, "Data xfer (cmd %d) error, status %d\n", cmd, ret);175		return ret;176	}177 178	/* Wait for completion of (read or write) DMA transfer */179	reg = (transfer == SD_CTL_DATA_XFER_READ) ?180		host->sdreader + LITEX_BLK2MEM_DONE :181		host->sdwriter + LITEX_MEM2BLK_DONE;182	ret = readx_poll_timeout(litex_read8, reg, evt, evt & SD_BIT_DONE,183				 SD_SLEEP_US, SD_TIMEOUT_US);184	if (ret)185		dev_err(dev, "DMA timeout (cmd %d)\n", cmd);186 187	return ret;188}189 190static int litex_mmc_send_app_cmd(struct litex_mmc_host *host)191{192	return litex_mmc_send_cmd(host, MMC_APP_CMD, host->rca << 16,193				  SD_CTL_RESP_SHORT, SD_CTL_DATA_XFER_NONE);194}195 196static int litex_mmc_send_set_bus_w_cmd(struct litex_mmc_host *host, u32 width)197{198	return litex_mmc_send_cmd(host, SD_APP_SET_BUS_WIDTH, width,199				  SD_CTL_RESP_SHORT, SD_CTL_DATA_XFER_NONE);200}201 202static int litex_mmc_set_bus_width(struct litex_mmc_host *host)203{204	bool app_cmd_sent;205	int ret;206 207	if (host->is_bus_width_set)208		return 0;209 210	/* Ensure 'app_cmd' precedes 'app_set_bus_width_cmd' */211	app_cmd_sent = host->app_cmd; /* was preceding command app_cmd? */212	if (!app_cmd_sent) {213		ret = litex_mmc_send_app_cmd(host);214		if (ret)215			return ret;216	}217 218	/* LiteSDCard only supports 4-bit bus width */219	ret = litex_mmc_send_set_bus_w_cmd(host, MMC_BUS_WIDTH_4);220	if (ret)221		return ret;222 223	/* Re-send 'app_cmd' if necessary */224	if (app_cmd_sent) {225		ret = litex_mmc_send_app_cmd(host);226		if (ret)227			return ret;228	}229 230	host->is_bus_width_set = true;231 232	return 0;233}234 235static int litex_mmc_get_cd(struct mmc_host *mmc)236{237	struct litex_mmc_host *host = mmc_priv(mmc);238	int ret;239 240	if (!mmc_card_is_removable(mmc))241		return 1;242 243	ret = !litex_read8(host->sdphy + LITEX_PHY_CARDDETECT);244	if (ret)245		return ret;246 247	/* Ensure bus width will be set (again) upon card (re)insertion */248	host->is_bus_width_set = false;249 250	return 0;251}252 253static irqreturn_t litex_mmc_interrupt(int irq, void *arg)254{255	struct mmc_host *mmc = arg;256	struct litex_mmc_host *host = mmc_priv(mmc);257	u32 pending = litex_read32(host->sdirq + LITEX_IRQ_PENDING);258	irqreturn_t ret = IRQ_NONE;259 260	/* Check for card change interrupt */261	if (pending & SDIRQ_CARD_DETECT) {262		litex_write32(host->sdirq + LITEX_IRQ_PENDING,263			      SDIRQ_CARD_DETECT);264		mmc_detect_change(mmc, msecs_to_jiffies(10));265		ret = IRQ_HANDLED;266	}267 268	/* Check for command completed */269	if (pending & SDIRQ_CMD_DONE) {270		/* Disable it so it doesn't keep interrupting */271		litex_write32(host->sdirq + LITEX_IRQ_ENABLE,272			      SDIRQ_CARD_DETECT);273		complete(&host->cmd_done);274		ret = IRQ_HANDLED;275	}276 277	return ret;278}279 280static u32 litex_mmc_response_len(struct mmc_command *cmd)281{282	if (cmd->flags & MMC_RSP_136)283		return SD_CTL_RESP_LONG;284	if (!(cmd->flags & MMC_RSP_PRESENT))285		return SD_CTL_RESP_NONE;286	if (cmd->flags & MMC_RSP_BUSY)287		return SD_CTL_RESP_SHORT_BUSY;288	return SD_CTL_RESP_SHORT;289}290 291static void litex_mmc_do_dma(struct litex_mmc_host *host, struct mmc_data *data,292			     unsigned int *len, bool *direct, u8 *transfer)293{294	struct device *dev = mmc_dev(host->mmc);295	dma_addr_t dma;296	int sg_count;297 298	/*299	 * Try to DMA directly to/from the data buffer.300	 * We can do that if the buffer can be mapped for DMA301	 * in one contiguous chunk.302	 */303	dma = host->dma;304	*len = data->blksz * data->blocks;305	sg_count = dma_map_sg(dev, data->sg, data->sg_len,306			      mmc_get_dma_dir(data));307	if (sg_count == 1) {308		dma = sg_dma_address(data->sg);309		*len = sg_dma_len(data->sg);310		*direct = true;311	} else if (*len > host->buf_size)312		*len = host->buf_size;313 314	if (data->flags & MMC_DATA_READ) {315		litex_write8(host->sdreader + LITEX_BLK2MEM_ENA, 0);316		litex_write64(host->sdreader + LITEX_BLK2MEM_BASE, dma);317		litex_write32(host->sdreader + LITEX_BLK2MEM_LEN, *len);318		litex_write8(host->sdreader + LITEX_BLK2MEM_ENA, 1);319		*transfer = SD_CTL_DATA_XFER_READ;320	} else if (data->flags & MMC_DATA_WRITE) {321		if (!*direct)322			sg_copy_to_buffer(data->sg, data->sg_len,323					  host->buffer, *len);324		litex_write8(host->sdwriter + LITEX_MEM2BLK_ENA, 0);325		litex_write64(host->sdwriter + LITEX_MEM2BLK_BASE, dma);326		litex_write32(host->sdwriter + LITEX_MEM2BLK_LEN, *len);327		litex_write8(host->sdwriter + LITEX_MEM2BLK_ENA, 1);328		*transfer = SD_CTL_DATA_XFER_WRITE;329	} else {330		dev_warn(dev, "Data present w/o read or write flag.\n");331		/* Continue: set cmd status, mark req done */332	}333 334	litex_write16(host->sdcore + LITEX_CORE_BLKLEN, data->blksz);335	litex_write32(host->sdcore + LITEX_CORE_BLKCNT, data->blocks);336}337 338static void litex_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)339{340	struct litex_mmc_host *host = mmc_priv(mmc);341	struct device *dev = mmc_dev(mmc);342	struct mmc_command *cmd = mrq->cmd;343	struct mmc_command *sbc = mrq->sbc;344	struct mmc_data *data = mrq->data;345	struct mmc_command *stop = mrq->stop;346	unsigned int retries = cmd->retries;347	unsigned int len = 0;348	bool direct = false;349	u32 response_len = litex_mmc_response_len(cmd);350	u8 transfer = SD_CTL_DATA_XFER_NONE;351 352	/* First check that the card is still there */353	if (!litex_mmc_get_cd(mmc)) {354		cmd->error = -ENOMEDIUM;355		mmc_request_done(mmc, mrq);356		return;357	}358 359	/* Send set-block-count command if needed */360	if (sbc) {361		sbc->error = litex_mmc_send_cmd(host, sbc->opcode, sbc->arg,362						litex_mmc_response_len(sbc),363						SD_CTL_DATA_XFER_NONE);364		if (sbc->error) {365			host->is_bus_width_set = false;366			mmc_request_done(mmc, mrq);367			return;368		}369	}370 371	if (data) {372		/*373		 * LiteSDCard only supports 4-bit bus width; therefore, we MUST374		 * inject a SET_BUS_WIDTH (acmd6) before the very first data375		 * transfer, earlier than when the mmc subsystem would normally376		 * get around to it!377		 */378		cmd->error = litex_mmc_set_bus_width(host);379		if (cmd->error) {380			dev_err(dev, "Can't set bus width!\n");381			mmc_request_done(mmc, mrq);382			return;383		}384 385		litex_mmc_do_dma(host, data, &len, &direct, &transfer);386	}387 388	do {389		cmd->error = litex_mmc_send_cmd(host, cmd->opcode, cmd->arg,390						response_len, transfer);391	} while (cmd->error && retries-- > 0);392 393	if (cmd->error) {394		/* Card may be gone; don't assume bus width is still set */395		host->is_bus_width_set = false;396	}397 398	if (response_len == SD_CTL_RESP_SHORT) {399		/* Pull short response fields from appropriate host registers */400		cmd->resp[0] = host->resp[3];401		cmd->resp[1] = host->resp[2] & 0xFF;402	} else if (response_len == SD_CTL_RESP_LONG) {403		cmd->resp[0] = host->resp[0];404		cmd->resp[1] = host->resp[1];405		cmd->resp[2] = host->resp[2];406		cmd->resp[3] = host->resp[3];407	}408 409	/* Send stop-transmission command if required */410	if (stop && (cmd->error || !sbc)) {411		stop->error = litex_mmc_send_cmd(host, stop->opcode, stop->arg,412						 litex_mmc_response_len(stop),413						 SD_CTL_DATA_XFER_NONE);414		if (stop->error)415			host->is_bus_width_set = false;416	}417 418	if (data) {419		dma_unmap_sg(dev, data->sg, data->sg_len,420			     mmc_get_dma_dir(data));421	}422 423	if (!cmd->error && transfer != SD_CTL_DATA_XFER_NONE) {424		data->bytes_xfered = min(len, mmc->max_req_size);425		if (transfer == SD_CTL_DATA_XFER_READ && !direct) {426			sg_copy_from_buffer(data->sg, sg_nents(data->sg),427					    host->buffer, data->bytes_xfered);428		}429	}430 431	mmc_request_done(mmc, mrq);432}433 434static void litex_mmc_setclk(struct litex_mmc_host *host, unsigned int freq)435{436	struct device *dev = mmc_dev(host->mmc);437	u32 div;438 439	div = freq ? host->ref_clk / freq : 256U;440	div = roundup_pow_of_two(div);441	div = clamp(div, 2U, 256U);442	dev_dbg(dev, "sd_clk_freq=%d: set to %d via div=%d\n",443		freq, host->ref_clk / div, div);444	litex_write16(host->sdphy + LITEX_PHY_CLOCKERDIV, div);445	host->sd_clk = freq;446}447 448static void litex_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)449{450	struct litex_mmc_host *host = mmc_priv(mmc);451 452	/*453	 * NOTE: Ignore any ios->bus_width updates; they occur right after454	 * the mmc core sends its own acmd6 bus-width change notification,455	 * which is redundant since we snoop on the command flow and inject456	 * an early acmd6 before the first data transfer command is sent!457	 */458 459	/* Update sd_clk */460	if (ios->clock != host->sd_clk)461		litex_mmc_setclk(host, ios->clock);462}463 464static const struct mmc_host_ops litex_mmc_ops = {465	.get_cd = litex_mmc_get_cd,466	.request = litex_mmc_request,467	.set_ios = litex_mmc_set_ios,468};469 470static int litex_mmc_irq_init(struct platform_device *pdev,471			      struct litex_mmc_host *host)472{473	struct device *dev = mmc_dev(host->mmc);474	int ret;475 476	ret = platform_get_irq_optional(pdev, 0);477	if (ret < 0 && ret != -ENXIO)478		return ret;479	if (ret > 0)480		host->irq = ret;481	else {482		dev_warn(dev, "Failed to get IRQ, using polling\n");483		goto use_polling;484	}485 486	host->sdirq = devm_platform_ioremap_resource_byname(pdev, "irq");487	if (IS_ERR(host->sdirq))488		return PTR_ERR(host->sdirq);489 490	ret = devm_request_irq(dev, host->irq, litex_mmc_interrupt, 0,491			       "litex-mmc", host->mmc);492	if (ret < 0) {493		dev_warn(dev, "IRQ request error %d, using polling\n", ret);494		goto use_polling;495	}496 497	/* Clear & enable card-change interrupts */498	litex_write32(host->sdirq + LITEX_IRQ_PENDING, SDIRQ_CARD_DETECT);499	litex_write32(host->sdirq + LITEX_IRQ_ENABLE, SDIRQ_CARD_DETECT);500 501	return 0;502 503use_polling:504	host->mmc->caps |= MMC_CAP_NEEDS_POLL;505	host->irq = 0;506	return 0;507}508 509static void litex_mmc_free_host_wrapper(void *mmc)510{511	mmc_free_host(mmc);512}513 514static int litex_mmc_probe(struct platform_device *pdev)515{516	struct device *dev = &pdev->dev;517	struct litex_mmc_host *host;518	struct mmc_host *mmc;519	struct clk *clk;520	int ret;521 522	/*523	 * NOTE: defaults to max_[req,seg]_size=PAGE_SIZE, max_blk_size=512,524	 * and max_blk_count accordingly set to 8;525	 * If for some reason we need to modify max_blk_count, we must also526	 * re-calculate `max_[req,seg]_size = max_blk_size * max_blk_count;`527	 */528	mmc = mmc_alloc_host(sizeof(struct litex_mmc_host), dev);529	if (!mmc)530		return -ENOMEM;531 532	ret = devm_add_action_or_reset(dev, litex_mmc_free_host_wrapper, mmc);533	if (ret)534		return dev_err_probe(dev, ret,535				     "Can't register mmc_free_host action\n");536 537	host = mmc_priv(mmc);538	host->mmc = mmc;539 540	/* Initialize clock source */541	clk = devm_clk_get(dev, NULL);542	if (IS_ERR(clk))543		return dev_err_probe(dev, PTR_ERR(clk), "can't get clock\n");544	host->ref_clk = clk_get_rate(clk);545	host->sd_clk = 0;546 547	/*548	 * LiteSDCard only supports 4-bit bus width; therefore, we MUST inject549	 * a SET_BUS_WIDTH (acmd6) before the very first data transfer, earlier550	 * than when the mmc subsystem would normally get around to it!551	 */552	host->is_bus_width_set = false;553	host->app_cmd = false;554 555	/* LiteSDCard can support 64-bit DMA addressing */556	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));557	if (ret)558		return ret;559 560	host->buf_size = mmc->max_req_size * 2;561	host->buffer = dmam_alloc_coherent(dev, host->buf_size,562					   &host->dma, GFP_KERNEL);563	if (host->buffer == NULL)564		return -ENOMEM;565 566	host->sdphy = devm_platform_ioremap_resource_byname(pdev, "phy");567	if (IS_ERR(host->sdphy))568		return PTR_ERR(host->sdphy);569 570	host->sdcore = devm_platform_ioremap_resource_byname(pdev, "core");571	if (IS_ERR(host->sdcore))572		return PTR_ERR(host->sdcore);573 574	host->sdreader = devm_platform_ioremap_resource_byname(pdev, "reader");575	if (IS_ERR(host->sdreader))576		return PTR_ERR(host->sdreader);577 578	host->sdwriter = devm_platform_ioremap_resource_byname(pdev, "writer");579	if (IS_ERR(host->sdwriter))580		return PTR_ERR(host->sdwriter);581 582	/* Ensure DMA bus masters are disabled */583	litex_write8(host->sdreader + LITEX_BLK2MEM_ENA, 0);584	litex_write8(host->sdwriter + LITEX_MEM2BLK_ENA, 0);585 586	init_completion(&host->cmd_done);587	ret = litex_mmc_irq_init(pdev, host);588	if (ret)589		return ret;590 591	mmc->ops = &litex_mmc_ops;592 593	ret = mmc_regulator_get_supply(mmc);594	if (ret || mmc->ocr_avail == 0) {595		dev_warn(dev, "can't get voltage, defaulting to 3.3V\n");596		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;597	}598 599	/*600	 * Set default sd_clk frequency range based on empirical observations601	 * of LiteSDCard gateware behavior on typical SDCard media602	 */603	mmc->f_min = 12.5e6;604	mmc->f_max = 50e6;605 606	ret = mmc_of_parse(mmc);607	if (ret)608		return ret;609 610	/* Force 4-bit bus_width (only width supported by hardware) */611	mmc->caps &= ~MMC_CAP_8_BIT_DATA;612	mmc->caps |= MMC_CAP_4_BIT_DATA;613 614	/* Set default capabilities */615	mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY |616		     MMC_CAP_DRIVER_TYPE_D |617		     MMC_CAP_CMD23;618	mmc->caps2 |= MMC_CAP2_NO_WRITE_PROTECT |619		      MMC_CAP2_NO_SDIO |620		      MMC_CAP2_NO_MMC;621 622	platform_set_drvdata(pdev, host);623 624	ret = mmc_add_host(mmc);625	if (ret)626		return ret;627 628	dev_info(dev, "LiteX MMC controller initialized.\n");629	return 0;630}631 632static void litex_mmc_remove(struct platform_device *pdev)633{634	struct litex_mmc_host *host = platform_get_drvdata(pdev);635 636	mmc_remove_host(host->mmc);637}638 639static const struct of_device_id litex_match[] = {640	{ .compatible = "litex,mmc" },641	{ }642};643MODULE_DEVICE_TABLE(of, litex_match);644 645static struct platform_driver litex_mmc_driver = {646	.probe = litex_mmc_probe,647	.remove_new = litex_mmc_remove,648	.driver = {649		.name = "litex-mmc",650		.of_match_table = litex_match,651		.probe_type = PROBE_PREFER_ASYNCHRONOUS,652	},653};654module_platform_driver(litex_mmc_driver);655 656MODULE_DESCRIPTION("LiteX SDCard driver");657MODULE_AUTHOR("Antmicro <contact@antmicro.com>");658MODULE_AUTHOR("Kamil Rakoczy <krakoczy@antmicro.com>");659MODULE_AUTHOR("Maciej Dudek <mdudek@internships.antmicro.com>");660MODULE_AUTHOR("Paul Mackerras <paulus@ozlabs.org>");661MODULE_AUTHOR("Gabriel Somlo <gsomlo@gmail.com>");662MODULE_LICENSE("GPL v2");663