cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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peci-aspeed.c (17679B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2// Copyright (c) 2012-2017 ASPEED Technology Inc.
      3// Copyright (c) 2018-2021 Intel Corporation
      4
      5#include <asm/unaligned.h>
      6
      7#include <linux/bitfield.h>
      8#include <linux/clk.h>
      9#include <linux/clkdev.h>
     10#include <linux/clk-provider.h>
     11#include <linux/delay.h>
     12#include <linux/interrupt.h>
     13#include <linux/io.h>
     14#include <linux/iopoll.h>
     15#include <linux/jiffies.h>
     16#include <linux/math.h>
     17#include <linux/module.h>
     18#include <linux/of.h>
     19#include <linux/peci.h>
     20#include <linux/platform_device.h>
     21#include <linux/reset.h>
     22
     23/* ASPEED PECI Registers */
     24/* Control Register */
     25#define ASPEED_PECI_CTRL			0x00
     26#define   ASPEED_PECI_CTRL_SAMPLING_MASK	GENMASK(19, 16)
     27#define   ASPEED_PECI_CTRL_RD_MODE_MASK		GENMASK(13, 12)
     28#define     ASPEED_PECI_CTRL_RD_MODE_DBG	BIT(13)
     29#define     ASPEED_PECI_CTRL_RD_MODE_COUNT	BIT(12)
     30#define   ASPEED_PECI_CTRL_CLK_SRC_HCLK		BIT(11)
     31#define   ASPEED_PECI_CTRL_CLK_DIV_MASK		GENMASK(10, 8)
     32#define   ASPEED_PECI_CTRL_INVERT_OUT		BIT(7)
     33#define   ASPEED_PECI_CTRL_INVERT_IN		BIT(6)
     34#define   ASPEED_PECI_CTRL_BUS_CONTENTION_EN	BIT(5)
     35#define   ASPEED_PECI_CTRL_PECI_EN		BIT(4)
     36#define   ASPEED_PECI_CTRL_PECI_CLK_EN		BIT(0)
     37
     38/* Timing Negotiation Register */
     39#define ASPEED_PECI_TIMING_NEGOTIATION		0x04
     40#define   ASPEED_PECI_T_NEGO_MSG_MASK		GENMASK(15, 8)
     41#define   ASPEED_PECI_T_NEGO_ADDR_MASK		GENMASK(7, 0)
     42
     43/* Command Register */
     44#define ASPEED_PECI_CMD				0x08
     45#define   ASPEED_PECI_CMD_PIN_MONITORING	BIT(31)
     46#define   ASPEED_PECI_CMD_STS_MASK		GENMASK(27, 24)
     47#define     ASPEED_PECI_CMD_STS_ADDR_T_NEGO	0x3
     48#define   ASPEED_PECI_CMD_IDLE_MASK		\
     49	  (ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING)
     50#define   ASPEED_PECI_CMD_FIRE			BIT(0)
     51
     52/* Read/Write Length Register */
     53#define ASPEED_PECI_RW_LENGTH			0x0c
     54#define   ASPEED_PECI_AW_FCS_EN			BIT(31)
     55#define   ASPEED_PECI_RD_LEN_MASK		GENMASK(23, 16)
     56#define   ASPEED_PECI_WR_LEN_MASK		GENMASK(15, 8)
     57#define   ASPEED_PECI_TARGET_ADDR_MASK		GENMASK(7, 0)
     58
     59/* Expected FCS Data Register */
     60#define ASPEED_PECI_EXPECTED_FCS		0x10
     61#define   ASPEED_PECI_EXPECTED_RD_FCS_MASK	GENMASK(23, 16)
     62#define   ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK	GENMASK(15, 8)
     63#define   ASPEED_PECI_EXPECTED_WR_FCS_MASK	GENMASK(7, 0)
     64
     65/* Captured FCS Data Register */
     66#define ASPEED_PECI_CAPTURED_FCS		0x14
     67#define   ASPEED_PECI_CAPTURED_RD_FCS_MASK	GENMASK(23, 16)
     68#define   ASPEED_PECI_CAPTURED_WR_FCS_MASK	GENMASK(7, 0)
     69
     70/* Interrupt Register */
     71#define ASPEED_PECI_INT_CTRL			0x18
     72#define   ASPEED_PECI_TIMING_NEGO_SEL_MASK	GENMASK(31, 30)
     73#define     ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO	0
     74#define     ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO	1
     75#define     ASPEED_PECI_MESSAGE_NEGO		2
     76#define   ASPEED_PECI_INT_MASK			GENMASK(4, 0)
     77#define     ASPEED_PECI_INT_BUS_TIMEOUT		BIT(4)
     78#define     ASPEED_PECI_INT_BUS_CONTENTION	BIT(3)
     79#define     ASPEED_PECI_INT_WR_FCS_BAD		BIT(2)
     80#define     ASPEED_PECI_INT_WR_FCS_ABORT	BIT(1)
     81#define     ASPEED_PECI_INT_CMD_DONE		BIT(0)
     82
     83/* Interrupt Status Register */
     84#define ASPEED_PECI_INT_STS			0x1c
     85#define   ASPEED_PECI_INT_TIMING_RESULT_MASK	GENMASK(29, 16)
     86	  /* bits[4..0]: Same bit fields in the 'Interrupt Register' */
     87
     88/* Rx/Tx Data Buffer Registers */
     89#define ASPEED_PECI_WR_DATA0			0x20
     90#define ASPEED_PECI_WR_DATA1			0x24
     91#define ASPEED_PECI_WR_DATA2			0x28
     92#define ASPEED_PECI_WR_DATA3			0x2c
     93#define ASPEED_PECI_RD_DATA0			0x30
     94#define ASPEED_PECI_RD_DATA1			0x34
     95#define ASPEED_PECI_RD_DATA2			0x38
     96#define ASPEED_PECI_RD_DATA3			0x3c
     97#define ASPEED_PECI_WR_DATA4			0x40
     98#define ASPEED_PECI_WR_DATA5			0x44
     99#define ASPEED_PECI_WR_DATA6			0x48
    100#define ASPEED_PECI_WR_DATA7			0x4c
    101#define ASPEED_PECI_RD_DATA4			0x50
    102#define ASPEED_PECI_RD_DATA5			0x54
    103#define ASPEED_PECI_RD_DATA6			0x58
    104#define ASPEED_PECI_RD_DATA7			0x5c
    105#define   ASPEED_PECI_DATA_BUF_SIZE_MAX		32
    106
    107/* Timing Negotiation */
    108#define ASPEED_PECI_CLK_FREQUENCY_MIN		2000
    109#define ASPEED_PECI_CLK_FREQUENCY_DEFAULT	1000000
    110#define ASPEED_PECI_CLK_FREQUENCY_MAX		2000000
    111#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT	8
    112/* Timeout */
    113#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US	(50 * USEC_PER_MSEC)
    114#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US	(10 * USEC_PER_MSEC)
    115#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT	1000
    116#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX		1000
    117
    118#define ASPEED_PECI_CLK_DIV1(msg_timing) (4 * (msg_timing) + 1)
    119#define ASPEED_PECI_CLK_DIV2(clk_div_exp) BIT(clk_div_exp)
    120#define ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp) \
    121	(4 * ASPEED_PECI_CLK_DIV1(msg_timing) * ASPEED_PECI_CLK_DIV2(clk_div_exp))
    122
    123struct aspeed_peci {
    124	struct peci_controller *controller;
    125	struct device *dev;
    126	void __iomem *base;
    127	struct reset_control *rst;
    128	int irq;
    129	spinlock_t lock; /* to sync completion status handling */
    130	struct completion xfer_complete;
    131	struct clk *clk;
    132	u32 clk_frequency;
    133	u32 status;
    134	u32 cmd_timeout_ms;
    135};
    136
    137struct clk_aspeed_peci {
    138	struct clk_hw hw;
    139	struct aspeed_peci *aspeed_peci;
    140};
    141
    142static void aspeed_peci_controller_enable(struct aspeed_peci *priv)
    143{
    144	u32 val = readl(priv->base + ASPEED_PECI_CTRL);
    145
    146	val |= ASPEED_PECI_CTRL_PECI_CLK_EN;
    147	val |= ASPEED_PECI_CTRL_PECI_EN;
    148
    149	writel(val, priv->base + ASPEED_PECI_CTRL);
    150}
    151
    152static void aspeed_peci_init_regs(struct aspeed_peci *priv)
    153{
    154	u32 val;
    155
    156	/* Clear interrupts */
    157	writel(ASPEED_PECI_INT_MASK, priv->base + ASPEED_PECI_INT_STS);
    158
    159	/* Set timing negotiation mode and enable interrupts */
    160	val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO);
    161	val |= ASPEED_PECI_INT_MASK;
    162	writel(val, priv->base + ASPEED_PECI_INT_CTRL);
    163
    164	val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT);
    165	writel(val, priv->base + ASPEED_PECI_CTRL);
    166}
    167
    168static int aspeed_peci_check_idle(struct aspeed_peci *priv)
    169{
    170	u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD);
    171	int ret;
    172
    173	/*
    174	 * Under normal circumstances, we expect to be idle here.
    175	 * In case there were any errors/timeouts that led to the situation
    176	 * where the hardware is not in idle state - we need to reset and
    177	 * reinitialize it to avoid potential controller hang.
    178	 */
    179	if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts)) {
    180		ret = reset_control_assert(priv->rst);
    181		if (ret) {
    182			dev_err(priv->dev, "cannot assert reset control\n");
    183			return ret;
    184		}
    185
    186		ret = reset_control_deassert(priv->rst);
    187		if (ret) {
    188			dev_err(priv->dev, "cannot deassert reset control\n");
    189			return ret;
    190		}
    191
    192		aspeed_peci_init_regs(priv);
    193
    194		ret = clk_set_rate(priv->clk, priv->clk_frequency);
    195		if (ret < 0) {
    196			dev_err(priv->dev, "cannot set clock frequency\n");
    197			return ret;
    198		}
    199
    200		aspeed_peci_controller_enable(priv);
    201	}
    202
    203	return readl_poll_timeout(priv->base + ASPEED_PECI_CMD,
    204				  cmd_sts,
    205				  !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK),
    206				  ASPEED_PECI_IDLE_CHECK_INTERVAL_US,
    207				  ASPEED_PECI_IDLE_CHECK_TIMEOUT_US);
    208}
    209
    210static int aspeed_peci_xfer(struct peci_controller *controller,
    211			    u8 addr, struct peci_request *req)
    212{
    213	struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent);
    214	unsigned long timeout = msecs_to_jiffies(priv->cmd_timeout_ms);
    215	u32 peci_head;
    216	int ret, i;
    217
    218	if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX ||
    219	    req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX)
    220		return -EINVAL;
    221
    222	/* Check command sts and bus idle state */
    223	ret = aspeed_peci_check_idle(priv);
    224	if (ret)
    225		return ret; /* -ETIMEDOUT */
    226
    227	spin_lock_irq(&priv->lock);
    228	reinit_completion(&priv->xfer_complete);
    229
    230	peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) |
    231		    FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) |
    232		    FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len);
    233
    234	writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH);
    235
    236	for (i = 0; i < req->tx.len; i += 4) {
    237		u32 reg = (i < 16 ? ASPEED_PECI_WR_DATA0 : ASPEED_PECI_WR_DATA4) + i % 16;
    238
    239		writel(get_unaligned_le32(&req->tx.buf[i]), priv->base + reg);
    240	}
    241
    242#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
    243	dev_dbg(priv->dev, "HEAD : %#08x\n", peci_head);
    244	print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req->tx.len);
    245#endif
    246
    247	priv->status = 0;
    248	writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD);
    249	spin_unlock_irq(&priv->lock);
    250
    251	ret = wait_for_completion_interruptible_timeout(&priv->xfer_complete, timeout);
    252	if (ret < 0)
    253		return ret;
    254
    255	if (ret == 0) {
    256		dev_dbg(priv->dev, "timeout waiting for a response\n");
    257		return -ETIMEDOUT;
    258	}
    259
    260	spin_lock_irq(&priv->lock);
    261
    262	if (priv->status != ASPEED_PECI_INT_CMD_DONE) {
    263		spin_unlock_irq(&priv->lock);
    264		dev_dbg(priv->dev, "no valid response, status: %#02x\n", priv->status);
    265		return -EIO;
    266	}
    267
    268	spin_unlock_irq(&priv->lock);
    269
    270	/*
    271	 * We need to use dword reads for register access, make sure that the
    272	 * buffer size is multiple of 4-bytes.
    273	 */
    274	BUILD_BUG_ON(PECI_REQUEST_MAX_BUF_SIZE % 4);
    275
    276	for (i = 0; i < req->rx.len; i += 4) {
    277		u32 reg = (i < 16 ? ASPEED_PECI_RD_DATA0 : ASPEED_PECI_RD_DATA4) + i % 16;
    278		u32 rx_data = readl(priv->base + reg);
    279
    280		put_unaligned_le32(rx_data, &req->rx.buf[i]);
    281	}
    282
    283#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
    284	print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req->rx.len);
    285#endif
    286	return 0;
    287}
    288
    289static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg)
    290{
    291	struct aspeed_peci *priv = arg;
    292	u32 status;
    293
    294	spin_lock(&priv->lock);
    295	status = readl(priv->base + ASPEED_PECI_INT_STS);
    296	writel(status, priv->base + ASPEED_PECI_INT_STS);
    297	priv->status |= (status & ASPEED_PECI_INT_MASK);
    298
    299	/*
    300	 * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE bit
    301	 * set even in an error case.
    302	 */
    303	if (status & ASPEED_PECI_INT_CMD_DONE)
    304		complete(&priv->xfer_complete);
    305
    306	writel(0, priv->base + ASPEED_PECI_CMD);
    307
    308	spin_unlock(&priv->lock);
    309
    310	return IRQ_HANDLED;
    311}
    312
    313static void clk_aspeed_peci_find_div_values(unsigned long rate, int *msg_timing, int *clk_div_exp)
    314{
    315	unsigned long best_diff = ~0ul, diff;
    316	int msg_timing_temp, clk_div_exp_temp, i, j;
    317
    318	for (i = 1; i <= 255; i++)
    319		for (j = 0; j < 8; j++) {
    320			diff = abs(rate - ASPEED_PECI_CLK_DIV1(i) * ASPEED_PECI_CLK_DIV2(j));
    321			if (diff < best_diff) {
    322				msg_timing_temp = i;
    323				clk_div_exp_temp = j;
    324				best_diff = diff;
    325			}
    326		}
    327
    328	*msg_timing = msg_timing_temp;
    329	*clk_div_exp = clk_div_exp_temp;
    330}
    331
    332static int clk_aspeed_peci_get_div(unsigned long rate, const unsigned long *prate)
    333{
    334	unsigned long this_rate = *prate / (4 * rate);
    335	int msg_timing, clk_div_exp;
    336
    337	clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp);
    338
    339	return ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp);
    340}
    341
    342static int clk_aspeed_peci_set_rate(struct clk_hw *hw, unsigned long rate,
    343				    unsigned long prate)
    344{
    345	struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw);
    346	struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci;
    347	unsigned long this_rate = prate / (4 * rate);
    348	int clk_div_exp, msg_timing;
    349	u32 val;
    350
    351	clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp);
    352
    353	val = readl(aspeed_peci->base + ASPEED_PECI_CTRL);
    354	val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, clk_div_exp);
    355	writel(val, aspeed_peci->base + ASPEED_PECI_CTRL);
    356
    357	val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, msg_timing);
    358	val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, msg_timing);
    359	writel(val, aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION);
    360
    361	return 0;
    362}
    363
    364static long clk_aspeed_peci_round_rate(struct clk_hw *hw, unsigned long rate,
    365				       unsigned long *prate)
    366{
    367	int div = clk_aspeed_peci_get_div(rate, prate);
    368
    369	return DIV_ROUND_UP_ULL(*prate, div);
    370}
    371
    372static unsigned long clk_aspeed_peci_recalc_rate(struct clk_hw *hw, unsigned long prate)
    373{
    374	struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw);
    375	struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci;
    376	int div, msg_timing, addr_timing, clk_div_exp;
    377	u32 reg;
    378
    379	reg = readl(aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION);
    380	msg_timing = FIELD_GET(ASPEED_PECI_T_NEGO_MSG_MASK, reg);
    381	addr_timing = FIELD_GET(ASPEED_PECI_T_NEGO_ADDR_MASK, reg);
    382
    383	if (msg_timing != addr_timing)
    384		return 0;
    385
    386	reg = readl(aspeed_peci->base + ASPEED_PECI_CTRL);
    387	clk_div_exp = FIELD_GET(ASPEED_PECI_CTRL_CLK_DIV_MASK, reg);
    388
    389	div = ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp);
    390
    391	return DIV_ROUND_UP_ULL(prate, div);
    392}
    393
    394static const struct clk_ops clk_aspeed_peci_ops = {
    395	.set_rate = clk_aspeed_peci_set_rate,
    396	.round_rate = clk_aspeed_peci_round_rate,
    397	.recalc_rate = clk_aspeed_peci_recalc_rate,
    398};
    399
    400/*
    401 * PECI HW contains a clock divider which is a combination of:
    402 *  div0: 4 (fixed divider)
    403 *  div1: x + 1
    404 *  div2: 1 << y
    405 * In other words, out_clk = in_clk / (div0 * div1 * div2)
    406 * The resulting frequency is used by PECI Controller to drive the PECI bus to
    407 * negotiate optimal transfer rate.
    408 */
    409static struct clk *devm_aspeed_peci_register_clk_div(struct device *dev, struct clk *parent,
    410						     struct aspeed_peci *priv)
    411{
    412	struct clk_aspeed_peci *peci_clk;
    413	struct clk_init_data init;
    414	const char *parent_name;
    415	char name[32];
    416	int ret;
    417
    418	snprintf(name, sizeof(name), "%s_div", dev_name(dev));
    419
    420	parent_name = __clk_get_name(parent);
    421
    422	init.ops = &clk_aspeed_peci_ops;
    423	init.name = name;
    424	init.parent_names = (const char* []) { parent_name };
    425	init.num_parents = 1;
    426	init.flags = 0;
    427
    428	peci_clk = devm_kzalloc(dev, sizeof(struct clk_aspeed_peci), GFP_KERNEL);
    429	if (!peci_clk)
    430		return ERR_PTR(-ENOMEM);
    431
    432	peci_clk->hw.init = &init;
    433	peci_clk->aspeed_peci = priv;
    434
    435	ret = devm_clk_hw_register(dev, &peci_clk->hw);
    436	if (ret)
    437		return ERR_PTR(ret);
    438
    439	return peci_clk->hw.clk;
    440}
    441
    442static void aspeed_peci_property_sanitize(struct device *dev, const char *propname,
    443					  u32 min, u32 max, u32 default_val, u32 *propval)
    444{
    445	u32 val;
    446	int ret;
    447
    448	ret = device_property_read_u32(dev, propname, &val);
    449	if (ret) {
    450		val = default_val;
    451	} else if (val > max || val < min) {
    452		dev_warn(dev, "invalid %s: %u, falling back to: %u\n",
    453			 propname, val, default_val);
    454
    455		val = default_val;
    456	}
    457
    458	*propval = val;
    459}
    460
    461static void aspeed_peci_property_setup(struct aspeed_peci *priv)
    462{
    463	aspeed_peci_property_sanitize(priv->dev, "clock-frequency",
    464				      ASPEED_PECI_CLK_FREQUENCY_MIN, ASPEED_PECI_CLK_FREQUENCY_MAX,
    465				      ASPEED_PECI_CLK_FREQUENCY_DEFAULT, &priv->clk_frequency);
    466	aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms",
    467				      1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX,
    468				      ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, &priv->cmd_timeout_ms);
    469}
    470
    471static struct peci_controller_ops aspeed_ops = {
    472	.xfer = aspeed_peci_xfer,
    473};
    474
    475static void aspeed_peci_reset_control_release(void *data)
    476{
    477	reset_control_assert(data);
    478}
    479
    480static int devm_aspeed_peci_reset_control_deassert(struct device *dev, struct reset_control *rst)
    481{
    482	int ret;
    483
    484	ret = reset_control_deassert(rst);
    485	if (ret)
    486		return ret;
    487
    488	return devm_add_action_or_reset(dev, aspeed_peci_reset_control_release, rst);
    489}
    490
    491static void aspeed_peci_clk_release(void *data)
    492{
    493	clk_disable_unprepare(data);
    494}
    495
    496static int devm_aspeed_peci_clk_enable(struct device *dev, struct clk *clk)
    497{
    498	int ret;
    499
    500	ret = clk_prepare_enable(clk);
    501	if (ret)
    502		return ret;
    503
    504	return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk);
    505}
    506
    507static int aspeed_peci_probe(struct platform_device *pdev)
    508{
    509	struct peci_controller *controller;
    510	struct aspeed_peci *priv;
    511	struct clk *ref_clk;
    512	int ret;
    513
    514	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
    515	if (!priv)
    516		return -ENOMEM;
    517
    518	priv->dev = &pdev->dev;
    519	dev_set_drvdata(priv->dev, priv);
    520
    521	priv->base = devm_platform_ioremap_resource(pdev, 0);
    522	if (IS_ERR(priv->base))
    523		return PTR_ERR(priv->base);
    524
    525	priv->irq = platform_get_irq(pdev, 0);
    526	if (!priv->irq)
    527		return priv->irq;
    528
    529	ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler,
    530			       0, "peci-aspeed", priv);
    531	if (ret)
    532		return ret;
    533
    534	init_completion(&priv->xfer_complete);
    535	spin_lock_init(&priv->lock);
    536
    537	priv->rst = devm_reset_control_get(&pdev->dev, NULL);
    538	if (IS_ERR(priv->rst))
    539		return dev_err_probe(priv->dev, PTR_ERR(priv->rst),
    540				     "failed to get reset control\n");
    541
    542	ret = devm_aspeed_peci_reset_control_deassert(priv->dev, priv->rst);
    543	if (ret)
    544		return dev_err_probe(priv->dev, ret, "cannot deassert reset control\n");
    545
    546	aspeed_peci_property_setup(priv);
    547
    548	aspeed_peci_init_regs(priv);
    549
    550	ref_clk = devm_clk_get(priv->dev, NULL);
    551	if (IS_ERR(ref_clk))
    552		return dev_err_probe(priv->dev, PTR_ERR(ref_clk), "failed to get ref clock\n");
    553
    554	priv->clk = devm_aspeed_peci_register_clk_div(priv->dev, ref_clk, priv);
    555	if (IS_ERR(priv->clk))
    556		return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "cannot register clock\n");
    557
    558	ret = clk_set_rate(priv->clk, priv->clk_frequency);
    559	if (ret < 0)
    560		return dev_err_probe(priv->dev, ret, "cannot set clock frequency\n");
    561
    562	ret = devm_aspeed_peci_clk_enable(priv->dev, priv->clk);
    563	if (ret)
    564		return dev_err_probe(priv->dev, ret, "failed to enable clock\n");
    565
    566	aspeed_peci_controller_enable(priv);
    567
    568	controller = devm_peci_controller_add(priv->dev, &aspeed_ops);
    569	if (IS_ERR(controller))
    570		return dev_err_probe(priv->dev, PTR_ERR(controller),
    571				     "failed to add aspeed peci controller\n");
    572
    573	priv->controller = controller;
    574
    575	return 0;
    576}
    577
    578static const struct of_device_id aspeed_peci_of_table[] = {
    579	{ .compatible = "aspeed,ast2400-peci", },
    580	{ .compatible = "aspeed,ast2500-peci", },
    581	{ .compatible = "aspeed,ast2600-peci", },
    582	{ }
    583};
    584MODULE_DEVICE_TABLE(of, aspeed_peci_of_table);
    585
    586static struct platform_driver aspeed_peci_driver = {
    587	.probe  = aspeed_peci_probe,
    588	.driver = {
    589		.name           = "peci-aspeed",
    590		.of_match_table = aspeed_peci_of_table,
    591	},
    592};
    593module_platform_driver(aspeed_peci_driver);
    594
    595MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
    596MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>");
    597MODULE_DESCRIPTION("ASPEED PECI driver");
    598MODULE_LICENSE("GPL");
    599MODULE_IMPORT_NS(PECI);