162306a36Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-only 262306a36Sopenharmony_ci// Copyright (c) 2012-2017 ASPEED Technology Inc. 362306a36Sopenharmony_ci// Copyright (c) 2018-2021 Intel Corporation 462306a36Sopenharmony_ci 562306a36Sopenharmony_ci#include <asm/unaligned.h> 662306a36Sopenharmony_ci 762306a36Sopenharmony_ci#include <linux/bitfield.h> 862306a36Sopenharmony_ci#include <linux/clk.h> 962306a36Sopenharmony_ci#include <linux/clkdev.h> 1062306a36Sopenharmony_ci#include <linux/clk-provider.h> 1162306a36Sopenharmony_ci#include <linux/delay.h> 1262306a36Sopenharmony_ci#include <linux/interrupt.h> 1362306a36Sopenharmony_ci#include <linux/io.h> 1462306a36Sopenharmony_ci#include <linux/iopoll.h> 1562306a36Sopenharmony_ci#include <linux/jiffies.h> 1662306a36Sopenharmony_ci#include <linux/math.h> 1762306a36Sopenharmony_ci#include <linux/module.h> 1862306a36Sopenharmony_ci#include <linux/of.h> 1962306a36Sopenharmony_ci#include <linux/peci.h> 2062306a36Sopenharmony_ci#include <linux/platform_device.h> 2162306a36Sopenharmony_ci#include <linux/reset.h> 2262306a36Sopenharmony_ci 2362306a36Sopenharmony_ci/* ASPEED PECI Registers */ 2462306a36Sopenharmony_ci/* Control Register */ 2562306a36Sopenharmony_ci#define ASPEED_PECI_CTRL 0x00 2662306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_SAMPLING_MASK GENMASK(19, 16) 2762306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_RD_MODE_MASK GENMASK(13, 12) 2862306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_RD_MODE_DBG BIT(13) 2962306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_RD_MODE_COUNT BIT(12) 3062306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_CLK_SRC_HCLK BIT(11) 3162306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8) 3262306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_INVERT_OUT BIT(7) 3362306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_INVERT_IN BIT(6) 3462306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_BUS_CONTENTION_EN BIT(5) 3562306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_PECI_EN BIT(4) 3662306a36Sopenharmony_ci#define ASPEED_PECI_CTRL_PECI_CLK_EN BIT(0) 3762306a36Sopenharmony_ci 3862306a36Sopenharmony_ci/* Timing Negotiation Register */ 3962306a36Sopenharmony_ci#define ASPEED_PECI_TIMING_NEGOTIATION 0x04 4062306a36Sopenharmony_ci#define ASPEED_PECI_T_NEGO_MSG_MASK GENMASK(15, 8) 4162306a36Sopenharmony_ci#define ASPEED_PECI_T_NEGO_ADDR_MASK GENMASK(7, 0) 4262306a36Sopenharmony_ci 4362306a36Sopenharmony_ci/* Command Register */ 4462306a36Sopenharmony_ci#define ASPEED_PECI_CMD 0x08 4562306a36Sopenharmony_ci#define ASPEED_PECI_CMD_PIN_MONITORING BIT(31) 4662306a36Sopenharmony_ci#define ASPEED_PECI_CMD_STS_MASK GENMASK(27, 24) 4762306a36Sopenharmony_ci#define ASPEED_PECI_CMD_STS_ADDR_T_NEGO 0x3 4862306a36Sopenharmony_ci#define ASPEED_PECI_CMD_IDLE_MASK \ 4962306a36Sopenharmony_ci (ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING) 5062306a36Sopenharmony_ci#define ASPEED_PECI_CMD_FIRE BIT(0) 5162306a36Sopenharmony_ci 5262306a36Sopenharmony_ci/* Read/Write Length Register */ 5362306a36Sopenharmony_ci#define ASPEED_PECI_RW_LENGTH 0x0c 5462306a36Sopenharmony_ci#define ASPEED_PECI_AW_FCS_EN BIT(31) 5562306a36Sopenharmony_ci#define ASPEED_PECI_RD_LEN_MASK GENMASK(23, 16) 5662306a36Sopenharmony_ci#define ASPEED_PECI_WR_LEN_MASK GENMASK(15, 8) 5762306a36Sopenharmony_ci#define ASPEED_PECI_TARGET_ADDR_MASK GENMASK(7, 0) 5862306a36Sopenharmony_ci 5962306a36Sopenharmony_ci/* Expected FCS Data Register */ 6062306a36Sopenharmony_ci#define ASPEED_PECI_EXPECTED_FCS 0x10 6162306a36Sopenharmony_ci#define ASPEED_PECI_EXPECTED_RD_FCS_MASK GENMASK(23, 16) 6262306a36Sopenharmony_ci#define ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK GENMASK(15, 8) 6362306a36Sopenharmony_ci#define ASPEED_PECI_EXPECTED_WR_FCS_MASK GENMASK(7, 0) 6462306a36Sopenharmony_ci 6562306a36Sopenharmony_ci/* Captured FCS Data Register */ 6662306a36Sopenharmony_ci#define ASPEED_PECI_CAPTURED_FCS 0x14 6762306a36Sopenharmony_ci#define ASPEED_PECI_CAPTURED_RD_FCS_MASK GENMASK(23, 16) 6862306a36Sopenharmony_ci#define ASPEED_PECI_CAPTURED_WR_FCS_MASK GENMASK(7, 0) 6962306a36Sopenharmony_ci 7062306a36Sopenharmony_ci/* Interrupt Register */ 7162306a36Sopenharmony_ci#define ASPEED_PECI_INT_CTRL 0x18 7262306a36Sopenharmony_ci#define ASPEED_PECI_TIMING_NEGO_SEL_MASK GENMASK(31, 30) 7362306a36Sopenharmony_ci#define ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO 0 7462306a36Sopenharmony_ci#define ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO 1 7562306a36Sopenharmony_ci#define ASPEED_PECI_MESSAGE_NEGO 2 7662306a36Sopenharmony_ci#define ASPEED_PECI_INT_MASK GENMASK(4, 0) 7762306a36Sopenharmony_ci#define ASPEED_PECI_INT_BUS_TIMEOUT BIT(4) 7862306a36Sopenharmony_ci#define ASPEED_PECI_INT_BUS_CONTENTION BIT(3) 7962306a36Sopenharmony_ci#define ASPEED_PECI_INT_WR_FCS_BAD BIT(2) 8062306a36Sopenharmony_ci#define ASPEED_PECI_INT_WR_FCS_ABORT BIT(1) 8162306a36Sopenharmony_ci#define ASPEED_PECI_INT_CMD_DONE BIT(0) 8262306a36Sopenharmony_ci 8362306a36Sopenharmony_ci/* Interrupt Status Register */ 8462306a36Sopenharmony_ci#define ASPEED_PECI_INT_STS 0x1c 8562306a36Sopenharmony_ci#define ASPEED_PECI_INT_TIMING_RESULT_MASK GENMASK(29, 16) 8662306a36Sopenharmony_ci /* bits[4..0]: Same bit fields in the 'Interrupt Register' */ 8762306a36Sopenharmony_ci 8862306a36Sopenharmony_ci/* Rx/Tx Data Buffer Registers */ 8962306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA0 0x20 9062306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA1 0x24 9162306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA2 0x28 9262306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA3 0x2c 9362306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA0 0x30 9462306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA1 0x34 9562306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA2 0x38 9662306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA3 0x3c 9762306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA4 0x40 9862306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA5 0x44 9962306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA6 0x48 10062306a36Sopenharmony_ci#define ASPEED_PECI_WR_DATA7 0x4c 10162306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA4 0x50 10262306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA5 0x54 10362306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA6 0x58 10462306a36Sopenharmony_ci#define ASPEED_PECI_RD_DATA7 0x5c 10562306a36Sopenharmony_ci#define ASPEED_PECI_DATA_BUF_SIZE_MAX 32 10662306a36Sopenharmony_ci 10762306a36Sopenharmony_ci/* Timing Negotiation */ 10862306a36Sopenharmony_ci#define ASPEED_PECI_CLK_FREQUENCY_MIN 2000 10962306a36Sopenharmony_ci#define ASPEED_PECI_CLK_FREQUENCY_DEFAULT 1000000 11062306a36Sopenharmony_ci#define ASPEED_PECI_CLK_FREQUENCY_MAX 2000000 11162306a36Sopenharmony_ci#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT 8 11262306a36Sopenharmony_ci/* Timeout */ 11362306a36Sopenharmony_ci#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US (50 * USEC_PER_MSEC) 11462306a36Sopenharmony_ci#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US (10 * USEC_PER_MSEC) 11562306a36Sopenharmony_ci#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT 1000 11662306a36Sopenharmony_ci#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX 1000 11762306a36Sopenharmony_ci 11862306a36Sopenharmony_ci#define ASPEED_PECI_CLK_DIV1(msg_timing) (4 * (msg_timing) + 1) 11962306a36Sopenharmony_ci#define ASPEED_PECI_CLK_DIV2(clk_div_exp) BIT(clk_div_exp) 12062306a36Sopenharmony_ci#define ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp) \ 12162306a36Sopenharmony_ci (4 * ASPEED_PECI_CLK_DIV1(msg_timing) * ASPEED_PECI_CLK_DIV2(clk_div_exp)) 12262306a36Sopenharmony_ci 12362306a36Sopenharmony_cistruct aspeed_peci { 12462306a36Sopenharmony_ci struct peci_controller *controller; 12562306a36Sopenharmony_ci struct device *dev; 12662306a36Sopenharmony_ci void __iomem *base; 12762306a36Sopenharmony_ci struct reset_control *rst; 12862306a36Sopenharmony_ci int irq; 12962306a36Sopenharmony_ci spinlock_t lock; /* to sync completion status handling */ 13062306a36Sopenharmony_ci struct completion xfer_complete; 13162306a36Sopenharmony_ci struct clk *clk; 13262306a36Sopenharmony_ci u32 clk_frequency; 13362306a36Sopenharmony_ci u32 status; 13462306a36Sopenharmony_ci u32 cmd_timeout_ms; 13562306a36Sopenharmony_ci}; 13662306a36Sopenharmony_ci 13762306a36Sopenharmony_cistruct clk_aspeed_peci { 13862306a36Sopenharmony_ci struct clk_hw hw; 13962306a36Sopenharmony_ci struct aspeed_peci *aspeed_peci; 14062306a36Sopenharmony_ci}; 14162306a36Sopenharmony_ci 14262306a36Sopenharmony_cistatic void aspeed_peci_controller_enable(struct aspeed_peci *priv) 14362306a36Sopenharmony_ci{ 14462306a36Sopenharmony_ci u32 val = readl(priv->base + ASPEED_PECI_CTRL); 14562306a36Sopenharmony_ci 14662306a36Sopenharmony_ci val |= ASPEED_PECI_CTRL_PECI_CLK_EN; 14762306a36Sopenharmony_ci val |= ASPEED_PECI_CTRL_PECI_EN; 14862306a36Sopenharmony_ci 14962306a36Sopenharmony_ci writel(val, priv->base + ASPEED_PECI_CTRL); 15062306a36Sopenharmony_ci} 15162306a36Sopenharmony_ci 15262306a36Sopenharmony_cistatic void aspeed_peci_init_regs(struct aspeed_peci *priv) 15362306a36Sopenharmony_ci{ 15462306a36Sopenharmony_ci u32 val; 15562306a36Sopenharmony_ci 15662306a36Sopenharmony_ci /* Clear interrupts */ 15762306a36Sopenharmony_ci writel(ASPEED_PECI_INT_MASK, priv->base + ASPEED_PECI_INT_STS); 15862306a36Sopenharmony_ci 15962306a36Sopenharmony_ci /* Set timing negotiation mode and enable interrupts */ 16062306a36Sopenharmony_ci val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO); 16162306a36Sopenharmony_ci val |= ASPEED_PECI_INT_MASK; 16262306a36Sopenharmony_ci writel(val, priv->base + ASPEED_PECI_INT_CTRL); 16362306a36Sopenharmony_ci 16462306a36Sopenharmony_ci val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT); 16562306a36Sopenharmony_ci writel(val, priv->base + ASPEED_PECI_CTRL); 16662306a36Sopenharmony_ci} 16762306a36Sopenharmony_ci 16862306a36Sopenharmony_cistatic int aspeed_peci_check_idle(struct aspeed_peci *priv) 16962306a36Sopenharmony_ci{ 17062306a36Sopenharmony_ci u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD); 17162306a36Sopenharmony_ci int ret; 17262306a36Sopenharmony_ci 17362306a36Sopenharmony_ci /* 17462306a36Sopenharmony_ci * Under normal circumstances, we expect to be idle here. 17562306a36Sopenharmony_ci * In case there were any errors/timeouts that led to the situation 17662306a36Sopenharmony_ci * where the hardware is not in idle state - we need to reset and 17762306a36Sopenharmony_ci * reinitialize it to avoid potential controller hang. 17862306a36Sopenharmony_ci */ 17962306a36Sopenharmony_ci if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts)) { 18062306a36Sopenharmony_ci ret = reset_control_assert(priv->rst); 18162306a36Sopenharmony_ci if (ret) { 18262306a36Sopenharmony_ci dev_err(priv->dev, "cannot assert reset control\n"); 18362306a36Sopenharmony_ci return ret; 18462306a36Sopenharmony_ci } 18562306a36Sopenharmony_ci 18662306a36Sopenharmony_ci ret = reset_control_deassert(priv->rst); 18762306a36Sopenharmony_ci if (ret) { 18862306a36Sopenharmony_ci dev_err(priv->dev, "cannot deassert reset control\n"); 18962306a36Sopenharmony_ci return ret; 19062306a36Sopenharmony_ci } 19162306a36Sopenharmony_ci 19262306a36Sopenharmony_ci aspeed_peci_init_regs(priv); 19362306a36Sopenharmony_ci 19462306a36Sopenharmony_ci ret = clk_set_rate(priv->clk, priv->clk_frequency); 19562306a36Sopenharmony_ci if (ret < 0) { 19662306a36Sopenharmony_ci dev_err(priv->dev, "cannot set clock frequency\n"); 19762306a36Sopenharmony_ci return ret; 19862306a36Sopenharmony_ci } 19962306a36Sopenharmony_ci 20062306a36Sopenharmony_ci aspeed_peci_controller_enable(priv); 20162306a36Sopenharmony_ci } 20262306a36Sopenharmony_ci 20362306a36Sopenharmony_ci return readl_poll_timeout(priv->base + ASPEED_PECI_CMD, 20462306a36Sopenharmony_ci cmd_sts, 20562306a36Sopenharmony_ci !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK), 20662306a36Sopenharmony_ci ASPEED_PECI_IDLE_CHECK_INTERVAL_US, 20762306a36Sopenharmony_ci ASPEED_PECI_IDLE_CHECK_TIMEOUT_US); 20862306a36Sopenharmony_ci} 20962306a36Sopenharmony_ci 21062306a36Sopenharmony_cistatic int aspeed_peci_xfer(struct peci_controller *controller, 21162306a36Sopenharmony_ci u8 addr, struct peci_request *req) 21262306a36Sopenharmony_ci{ 21362306a36Sopenharmony_ci struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent); 21462306a36Sopenharmony_ci unsigned long timeout = msecs_to_jiffies(priv->cmd_timeout_ms); 21562306a36Sopenharmony_ci u32 peci_head; 21662306a36Sopenharmony_ci int ret, i; 21762306a36Sopenharmony_ci 21862306a36Sopenharmony_ci if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || 21962306a36Sopenharmony_ci req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) 22062306a36Sopenharmony_ci return -EINVAL; 22162306a36Sopenharmony_ci 22262306a36Sopenharmony_ci /* Check command sts and bus idle state */ 22362306a36Sopenharmony_ci ret = aspeed_peci_check_idle(priv); 22462306a36Sopenharmony_ci if (ret) 22562306a36Sopenharmony_ci return ret; /* -ETIMEDOUT */ 22662306a36Sopenharmony_ci 22762306a36Sopenharmony_ci spin_lock_irq(&priv->lock); 22862306a36Sopenharmony_ci reinit_completion(&priv->xfer_complete); 22962306a36Sopenharmony_ci 23062306a36Sopenharmony_ci peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | 23162306a36Sopenharmony_ci FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | 23262306a36Sopenharmony_ci FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); 23362306a36Sopenharmony_ci 23462306a36Sopenharmony_ci writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); 23562306a36Sopenharmony_ci 23662306a36Sopenharmony_ci for (i = 0; i < req->tx.len; i += 4) { 23762306a36Sopenharmony_ci u32 reg = (i < 16 ? ASPEED_PECI_WR_DATA0 : ASPEED_PECI_WR_DATA4) + i % 16; 23862306a36Sopenharmony_ci 23962306a36Sopenharmony_ci writel(get_unaligned_le32(&req->tx.buf[i]), priv->base + reg); 24062306a36Sopenharmony_ci } 24162306a36Sopenharmony_ci 24262306a36Sopenharmony_ci#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG) 24362306a36Sopenharmony_ci dev_dbg(priv->dev, "HEAD : %#08x\n", peci_head); 24462306a36Sopenharmony_ci print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req->tx.len); 24562306a36Sopenharmony_ci#endif 24662306a36Sopenharmony_ci 24762306a36Sopenharmony_ci priv->status = 0; 24862306a36Sopenharmony_ci writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); 24962306a36Sopenharmony_ci spin_unlock_irq(&priv->lock); 25062306a36Sopenharmony_ci 25162306a36Sopenharmony_ci ret = wait_for_completion_interruptible_timeout(&priv->xfer_complete, timeout); 25262306a36Sopenharmony_ci if (ret < 0) 25362306a36Sopenharmony_ci return ret; 25462306a36Sopenharmony_ci 25562306a36Sopenharmony_ci if (ret == 0) { 25662306a36Sopenharmony_ci dev_dbg(priv->dev, "timeout waiting for a response\n"); 25762306a36Sopenharmony_ci return -ETIMEDOUT; 25862306a36Sopenharmony_ci } 25962306a36Sopenharmony_ci 26062306a36Sopenharmony_ci spin_lock_irq(&priv->lock); 26162306a36Sopenharmony_ci 26262306a36Sopenharmony_ci if (priv->status != ASPEED_PECI_INT_CMD_DONE) { 26362306a36Sopenharmony_ci spin_unlock_irq(&priv->lock); 26462306a36Sopenharmony_ci dev_dbg(priv->dev, "no valid response, status: %#02x\n", priv->status); 26562306a36Sopenharmony_ci return -EIO; 26662306a36Sopenharmony_ci } 26762306a36Sopenharmony_ci 26862306a36Sopenharmony_ci spin_unlock_irq(&priv->lock); 26962306a36Sopenharmony_ci 27062306a36Sopenharmony_ci /* 27162306a36Sopenharmony_ci * We need to use dword reads for register access, make sure that the 27262306a36Sopenharmony_ci * buffer size is multiple of 4-bytes. 27362306a36Sopenharmony_ci */ 27462306a36Sopenharmony_ci BUILD_BUG_ON(PECI_REQUEST_MAX_BUF_SIZE % 4); 27562306a36Sopenharmony_ci 27662306a36Sopenharmony_ci for (i = 0; i < req->rx.len; i += 4) { 27762306a36Sopenharmony_ci u32 reg = (i < 16 ? ASPEED_PECI_RD_DATA0 : ASPEED_PECI_RD_DATA4) + i % 16; 27862306a36Sopenharmony_ci u32 rx_data = readl(priv->base + reg); 27962306a36Sopenharmony_ci 28062306a36Sopenharmony_ci put_unaligned_le32(rx_data, &req->rx.buf[i]); 28162306a36Sopenharmony_ci } 28262306a36Sopenharmony_ci 28362306a36Sopenharmony_ci#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG) 28462306a36Sopenharmony_ci print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req->rx.len); 28562306a36Sopenharmony_ci#endif 28662306a36Sopenharmony_ci return 0; 28762306a36Sopenharmony_ci} 28862306a36Sopenharmony_ci 28962306a36Sopenharmony_cistatic irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) 29062306a36Sopenharmony_ci{ 29162306a36Sopenharmony_ci struct aspeed_peci *priv = arg; 29262306a36Sopenharmony_ci u32 status; 29362306a36Sopenharmony_ci 29462306a36Sopenharmony_ci spin_lock(&priv->lock); 29562306a36Sopenharmony_ci status = readl(priv->base + ASPEED_PECI_INT_STS); 29662306a36Sopenharmony_ci writel(status, priv->base + ASPEED_PECI_INT_STS); 29762306a36Sopenharmony_ci priv->status |= (status & ASPEED_PECI_INT_MASK); 29862306a36Sopenharmony_ci 29962306a36Sopenharmony_ci /* 30062306a36Sopenharmony_ci * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE bit 30162306a36Sopenharmony_ci * set even in an error case. 30262306a36Sopenharmony_ci */ 30362306a36Sopenharmony_ci if (status & ASPEED_PECI_INT_CMD_DONE) 30462306a36Sopenharmony_ci complete(&priv->xfer_complete); 30562306a36Sopenharmony_ci 30662306a36Sopenharmony_ci writel(0, priv->base + ASPEED_PECI_CMD); 30762306a36Sopenharmony_ci 30862306a36Sopenharmony_ci spin_unlock(&priv->lock); 30962306a36Sopenharmony_ci 31062306a36Sopenharmony_ci return IRQ_HANDLED; 31162306a36Sopenharmony_ci} 31262306a36Sopenharmony_ci 31362306a36Sopenharmony_cistatic void clk_aspeed_peci_find_div_values(unsigned long rate, int *msg_timing, int *clk_div_exp) 31462306a36Sopenharmony_ci{ 31562306a36Sopenharmony_ci unsigned long best_diff = ~0ul, diff; 31662306a36Sopenharmony_ci int msg_timing_temp, clk_div_exp_temp, i, j; 31762306a36Sopenharmony_ci 31862306a36Sopenharmony_ci for (i = 1; i <= 255; i++) 31962306a36Sopenharmony_ci for (j = 0; j < 8; j++) { 32062306a36Sopenharmony_ci diff = abs(rate - ASPEED_PECI_CLK_DIV1(i) * ASPEED_PECI_CLK_DIV2(j)); 32162306a36Sopenharmony_ci if (diff < best_diff) { 32262306a36Sopenharmony_ci msg_timing_temp = i; 32362306a36Sopenharmony_ci clk_div_exp_temp = j; 32462306a36Sopenharmony_ci best_diff = diff; 32562306a36Sopenharmony_ci } 32662306a36Sopenharmony_ci } 32762306a36Sopenharmony_ci 32862306a36Sopenharmony_ci *msg_timing = msg_timing_temp; 32962306a36Sopenharmony_ci *clk_div_exp = clk_div_exp_temp; 33062306a36Sopenharmony_ci} 33162306a36Sopenharmony_ci 33262306a36Sopenharmony_cistatic int clk_aspeed_peci_get_div(unsigned long rate, const unsigned long *prate) 33362306a36Sopenharmony_ci{ 33462306a36Sopenharmony_ci unsigned long this_rate = *prate / (4 * rate); 33562306a36Sopenharmony_ci int msg_timing, clk_div_exp; 33662306a36Sopenharmony_ci 33762306a36Sopenharmony_ci clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp); 33862306a36Sopenharmony_ci 33962306a36Sopenharmony_ci return ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp); 34062306a36Sopenharmony_ci} 34162306a36Sopenharmony_ci 34262306a36Sopenharmony_cistatic int clk_aspeed_peci_set_rate(struct clk_hw *hw, unsigned long rate, 34362306a36Sopenharmony_ci unsigned long prate) 34462306a36Sopenharmony_ci{ 34562306a36Sopenharmony_ci struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw); 34662306a36Sopenharmony_ci struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci; 34762306a36Sopenharmony_ci unsigned long this_rate = prate / (4 * rate); 34862306a36Sopenharmony_ci int clk_div_exp, msg_timing; 34962306a36Sopenharmony_ci u32 val; 35062306a36Sopenharmony_ci 35162306a36Sopenharmony_ci clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp); 35262306a36Sopenharmony_ci 35362306a36Sopenharmony_ci val = readl(aspeed_peci->base + ASPEED_PECI_CTRL); 35462306a36Sopenharmony_ci val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, clk_div_exp); 35562306a36Sopenharmony_ci writel(val, aspeed_peci->base + ASPEED_PECI_CTRL); 35662306a36Sopenharmony_ci 35762306a36Sopenharmony_ci val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, msg_timing); 35862306a36Sopenharmony_ci val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, msg_timing); 35962306a36Sopenharmony_ci writel(val, aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION); 36062306a36Sopenharmony_ci 36162306a36Sopenharmony_ci return 0; 36262306a36Sopenharmony_ci} 36362306a36Sopenharmony_ci 36462306a36Sopenharmony_cistatic long clk_aspeed_peci_round_rate(struct clk_hw *hw, unsigned long rate, 36562306a36Sopenharmony_ci unsigned long *prate) 36662306a36Sopenharmony_ci{ 36762306a36Sopenharmony_ci int div = clk_aspeed_peci_get_div(rate, prate); 36862306a36Sopenharmony_ci 36962306a36Sopenharmony_ci return DIV_ROUND_UP_ULL(*prate, div); 37062306a36Sopenharmony_ci} 37162306a36Sopenharmony_ci 37262306a36Sopenharmony_cistatic unsigned long clk_aspeed_peci_recalc_rate(struct clk_hw *hw, unsigned long prate) 37362306a36Sopenharmony_ci{ 37462306a36Sopenharmony_ci struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw); 37562306a36Sopenharmony_ci struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci; 37662306a36Sopenharmony_ci int div, msg_timing, addr_timing, clk_div_exp; 37762306a36Sopenharmony_ci u32 reg; 37862306a36Sopenharmony_ci 37962306a36Sopenharmony_ci reg = readl(aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION); 38062306a36Sopenharmony_ci msg_timing = FIELD_GET(ASPEED_PECI_T_NEGO_MSG_MASK, reg); 38162306a36Sopenharmony_ci addr_timing = FIELD_GET(ASPEED_PECI_T_NEGO_ADDR_MASK, reg); 38262306a36Sopenharmony_ci 38362306a36Sopenharmony_ci if (msg_timing != addr_timing) 38462306a36Sopenharmony_ci return 0; 38562306a36Sopenharmony_ci 38662306a36Sopenharmony_ci reg = readl(aspeed_peci->base + ASPEED_PECI_CTRL); 38762306a36Sopenharmony_ci clk_div_exp = FIELD_GET(ASPEED_PECI_CTRL_CLK_DIV_MASK, reg); 38862306a36Sopenharmony_ci 38962306a36Sopenharmony_ci div = ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp); 39062306a36Sopenharmony_ci 39162306a36Sopenharmony_ci return DIV_ROUND_UP_ULL(prate, div); 39262306a36Sopenharmony_ci} 39362306a36Sopenharmony_ci 39462306a36Sopenharmony_cistatic const struct clk_ops clk_aspeed_peci_ops = { 39562306a36Sopenharmony_ci .set_rate = clk_aspeed_peci_set_rate, 39662306a36Sopenharmony_ci .round_rate = clk_aspeed_peci_round_rate, 39762306a36Sopenharmony_ci .recalc_rate = clk_aspeed_peci_recalc_rate, 39862306a36Sopenharmony_ci}; 39962306a36Sopenharmony_ci 40062306a36Sopenharmony_ci/* 40162306a36Sopenharmony_ci * PECI HW contains a clock divider which is a combination of: 40262306a36Sopenharmony_ci * div0: 4 (fixed divider) 40362306a36Sopenharmony_ci * div1: x + 1 40462306a36Sopenharmony_ci * div2: 1 << y 40562306a36Sopenharmony_ci * In other words, out_clk = in_clk / (div0 * div1 * div2) 40662306a36Sopenharmony_ci * The resulting frequency is used by PECI Controller to drive the PECI bus to 40762306a36Sopenharmony_ci * negotiate optimal transfer rate. 40862306a36Sopenharmony_ci */ 40962306a36Sopenharmony_cistatic struct clk *devm_aspeed_peci_register_clk_div(struct device *dev, struct clk *parent, 41062306a36Sopenharmony_ci struct aspeed_peci *priv) 41162306a36Sopenharmony_ci{ 41262306a36Sopenharmony_ci struct clk_aspeed_peci *peci_clk; 41362306a36Sopenharmony_ci struct clk_init_data init; 41462306a36Sopenharmony_ci const char *parent_name; 41562306a36Sopenharmony_ci char name[32]; 41662306a36Sopenharmony_ci int ret; 41762306a36Sopenharmony_ci 41862306a36Sopenharmony_ci snprintf(name, sizeof(name), "%s_div", dev_name(dev)); 41962306a36Sopenharmony_ci 42062306a36Sopenharmony_ci parent_name = __clk_get_name(parent); 42162306a36Sopenharmony_ci 42262306a36Sopenharmony_ci init.ops = &clk_aspeed_peci_ops; 42362306a36Sopenharmony_ci init.name = name; 42462306a36Sopenharmony_ci init.parent_names = (const char* []) { parent_name }; 42562306a36Sopenharmony_ci init.num_parents = 1; 42662306a36Sopenharmony_ci init.flags = 0; 42762306a36Sopenharmony_ci 42862306a36Sopenharmony_ci peci_clk = devm_kzalloc(dev, sizeof(struct clk_aspeed_peci), GFP_KERNEL); 42962306a36Sopenharmony_ci if (!peci_clk) 43062306a36Sopenharmony_ci return ERR_PTR(-ENOMEM); 43162306a36Sopenharmony_ci 43262306a36Sopenharmony_ci peci_clk->hw.init = &init; 43362306a36Sopenharmony_ci peci_clk->aspeed_peci = priv; 43462306a36Sopenharmony_ci 43562306a36Sopenharmony_ci ret = devm_clk_hw_register(dev, &peci_clk->hw); 43662306a36Sopenharmony_ci if (ret) 43762306a36Sopenharmony_ci return ERR_PTR(ret); 43862306a36Sopenharmony_ci 43962306a36Sopenharmony_ci return peci_clk->hw.clk; 44062306a36Sopenharmony_ci} 44162306a36Sopenharmony_ci 44262306a36Sopenharmony_cistatic void aspeed_peci_property_sanitize(struct device *dev, const char *propname, 44362306a36Sopenharmony_ci u32 min, u32 max, u32 default_val, u32 *propval) 44462306a36Sopenharmony_ci{ 44562306a36Sopenharmony_ci u32 val; 44662306a36Sopenharmony_ci int ret; 44762306a36Sopenharmony_ci 44862306a36Sopenharmony_ci ret = device_property_read_u32(dev, propname, &val); 44962306a36Sopenharmony_ci if (ret) { 45062306a36Sopenharmony_ci val = default_val; 45162306a36Sopenharmony_ci } else if (val > max || val < min) { 45262306a36Sopenharmony_ci dev_warn(dev, "invalid %s: %u, falling back to: %u\n", 45362306a36Sopenharmony_ci propname, val, default_val); 45462306a36Sopenharmony_ci 45562306a36Sopenharmony_ci val = default_val; 45662306a36Sopenharmony_ci } 45762306a36Sopenharmony_ci 45862306a36Sopenharmony_ci *propval = val; 45962306a36Sopenharmony_ci} 46062306a36Sopenharmony_ci 46162306a36Sopenharmony_cistatic void aspeed_peci_property_setup(struct aspeed_peci *priv) 46262306a36Sopenharmony_ci{ 46362306a36Sopenharmony_ci aspeed_peci_property_sanitize(priv->dev, "clock-frequency", 46462306a36Sopenharmony_ci ASPEED_PECI_CLK_FREQUENCY_MIN, ASPEED_PECI_CLK_FREQUENCY_MAX, 46562306a36Sopenharmony_ci ASPEED_PECI_CLK_FREQUENCY_DEFAULT, &priv->clk_frequency); 46662306a36Sopenharmony_ci aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms", 46762306a36Sopenharmony_ci 1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX, 46862306a36Sopenharmony_ci ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, &priv->cmd_timeout_ms); 46962306a36Sopenharmony_ci} 47062306a36Sopenharmony_ci 47162306a36Sopenharmony_cistatic const struct peci_controller_ops aspeed_ops = { 47262306a36Sopenharmony_ci .xfer = aspeed_peci_xfer, 47362306a36Sopenharmony_ci}; 47462306a36Sopenharmony_ci 47562306a36Sopenharmony_cistatic void aspeed_peci_reset_control_release(void *data) 47662306a36Sopenharmony_ci{ 47762306a36Sopenharmony_ci reset_control_assert(data); 47862306a36Sopenharmony_ci} 47962306a36Sopenharmony_ci 48062306a36Sopenharmony_cistatic int devm_aspeed_peci_reset_control_deassert(struct device *dev, struct reset_control *rst) 48162306a36Sopenharmony_ci{ 48262306a36Sopenharmony_ci int ret; 48362306a36Sopenharmony_ci 48462306a36Sopenharmony_ci ret = reset_control_deassert(rst); 48562306a36Sopenharmony_ci if (ret) 48662306a36Sopenharmony_ci return ret; 48762306a36Sopenharmony_ci 48862306a36Sopenharmony_ci return devm_add_action_or_reset(dev, aspeed_peci_reset_control_release, rst); 48962306a36Sopenharmony_ci} 49062306a36Sopenharmony_ci 49162306a36Sopenharmony_cistatic void aspeed_peci_clk_release(void *data) 49262306a36Sopenharmony_ci{ 49362306a36Sopenharmony_ci clk_disable_unprepare(data); 49462306a36Sopenharmony_ci} 49562306a36Sopenharmony_ci 49662306a36Sopenharmony_cistatic int devm_aspeed_peci_clk_enable(struct device *dev, struct clk *clk) 49762306a36Sopenharmony_ci{ 49862306a36Sopenharmony_ci int ret; 49962306a36Sopenharmony_ci 50062306a36Sopenharmony_ci ret = clk_prepare_enable(clk); 50162306a36Sopenharmony_ci if (ret) 50262306a36Sopenharmony_ci return ret; 50362306a36Sopenharmony_ci 50462306a36Sopenharmony_ci return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk); 50562306a36Sopenharmony_ci} 50662306a36Sopenharmony_ci 50762306a36Sopenharmony_cistatic int aspeed_peci_probe(struct platform_device *pdev) 50862306a36Sopenharmony_ci{ 50962306a36Sopenharmony_ci struct peci_controller *controller; 51062306a36Sopenharmony_ci struct aspeed_peci *priv; 51162306a36Sopenharmony_ci struct clk *ref_clk; 51262306a36Sopenharmony_ci int ret; 51362306a36Sopenharmony_ci 51462306a36Sopenharmony_ci priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 51562306a36Sopenharmony_ci if (!priv) 51662306a36Sopenharmony_ci return -ENOMEM; 51762306a36Sopenharmony_ci 51862306a36Sopenharmony_ci priv->dev = &pdev->dev; 51962306a36Sopenharmony_ci dev_set_drvdata(priv->dev, priv); 52062306a36Sopenharmony_ci 52162306a36Sopenharmony_ci priv->base = devm_platform_ioremap_resource(pdev, 0); 52262306a36Sopenharmony_ci if (IS_ERR(priv->base)) 52362306a36Sopenharmony_ci return PTR_ERR(priv->base); 52462306a36Sopenharmony_ci 52562306a36Sopenharmony_ci priv->irq = platform_get_irq(pdev, 0); 52662306a36Sopenharmony_ci if (priv->irq < 0) 52762306a36Sopenharmony_ci return priv->irq; 52862306a36Sopenharmony_ci 52962306a36Sopenharmony_ci ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler, 53062306a36Sopenharmony_ci 0, "peci-aspeed", priv); 53162306a36Sopenharmony_ci if (ret) 53262306a36Sopenharmony_ci return ret; 53362306a36Sopenharmony_ci 53462306a36Sopenharmony_ci init_completion(&priv->xfer_complete); 53562306a36Sopenharmony_ci spin_lock_init(&priv->lock); 53662306a36Sopenharmony_ci 53762306a36Sopenharmony_ci priv->rst = devm_reset_control_get(&pdev->dev, NULL); 53862306a36Sopenharmony_ci if (IS_ERR(priv->rst)) 53962306a36Sopenharmony_ci return dev_err_probe(priv->dev, PTR_ERR(priv->rst), 54062306a36Sopenharmony_ci "failed to get reset control\n"); 54162306a36Sopenharmony_ci 54262306a36Sopenharmony_ci ret = devm_aspeed_peci_reset_control_deassert(priv->dev, priv->rst); 54362306a36Sopenharmony_ci if (ret) 54462306a36Sopenharmony_ci return dev_err_probe(priv->dev, ret, "cannot deassert reset control\n"); 54562306a36Sopenharmony_ci 54662306a36Sopenharmony_ci aspeed_peci_property_setup(priv); 54762306a36Sopenharmony_ci 54862306a36Sopenharmony_ci aspeed_peci_init_regs(priv); 54962306a36Sopenharmony_ci 55062306a36Sopenharmony_ci ref_clk = devm_clk_get(priv->dev, NULL); 55162306a36Sopenharmony_ci if (IS_ERR(ref_clk)) 55262306a36Sopenharmony_ci return dev_err_probe(priv->dev, PTR_ERR(ref_clk), "failed to get ref clock\n"); 55362306a36Sopenharmony_ci 55462306a36Sopenharmony_ci priv->clk = devm_aspeed_peci_register_clk_div(priv->dev, ref_clk, priv); 55562306a36Sopenharmony_ci if (IS_ERR(priv->clk)) 55662306a36Sopenharmony_ci return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "cannot register clock\n"); 55762306a36Sopenharmony_ci 55862306a36Sopenharmony_ci ret = clk_set_rate(priv->clk, priv->clk_frequency); 55962306a36Sopenharmony_ci if (ret < 0) 56062306a36Sopenharmony_ci return dev_err_probe(priv->dev, ret, "cannot set clock frequency\n"); 56162306a36Sopenharmony_ci 56262306a36Sopenharmony_ci ret = devm_aspeed_peci_clk_enable(priv->dev, priv->clk); 56362306a36Sopenharmony_ci if (ret) 56462306a36Sopenharmony_ci return dev_err_probe(priv->dev, ret, "failed to enable clock\n"); 56562306a36Sopenharmony_ci 56662306a36Sopenharmony_ci aspeed_peci_controller_enable(priv); 56762306a36Sopenharmony_ci 56862306a36Sopenharmony_ci controller = devm_peci_controller_add(priv->dev, &aspeed_ops); 56962306a36Sopenharmony_ci if (IS_ERR(controller)) 57062306a36Sopenharmony_ci return dev_err_probe(priv->dev, PTR_ERR(controller), 57162306a36Sopenharmony_ci "failed to add aspeed peci controller\n"); 57262306a36Sopenharmony_ci 57362306a36Sopenharmony_ci priv->controller = controller; 57462306a36Sopenharmony_ci 57562306a36Sopenharmony_ci return 0; 57662306a36Sopenharmony_ci} 57762306a36Sopenharmony_ci 57862306a36Sopenharmony_cistatic const struct of_device_id aspeed_peci_of_table[] = { 57962306a36Sopenharmony_ci { .compatible = "aspeed,ast2400-peci", }, 58062306a36Sopenharmony_ci { .compatible = "aspeed,ast2500-peci", }, 58162306a36Sopenharmony_ci { .compatible = "aspeed,ast2600-peci", }, 58262306a36Sopenharmony_ci { } 58362306a36Sopenharmony_ci}; 58462306a36Sopenharmony_ciMODULE_DEVICE_TABLE(of, aspeed_peci_of_table); 58562306a36Sopenharmony_ci 58662306a36Sopenharmony_cistatic struct platform_driver aspeed_peci_driver = { 58762306a36Sopenharmony_ci .probe = aspeed_peci_probe, 58862306a36Sopenharmony_ci .driver = { 58962306a36Sopenharmony_ci .name = "peci-aspeed", 59062306a36Sopenharmony_ci .of_match_table = aspeed_peci_of_table, 59162306a36Sopenharmony_ci }, 59262306a36Sopenharmony_ci}; 59362306a36Sopenharmony_cimodule_platform_driver(aspeed_peci_driver); 59462306a36Sopenharmony_ci 59562306a36Sopenharmony_ciMODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>"); 59662306a36Sopenharmony_ciMODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>"); 59762306a36Sopenharmony_ciMODULE_DESCRIPTION("ASPEED PECI driver"); 59862306a36Sopenharmony_ciMODULE_LICENSE("GPL"); 59962306a36Sopenharmony_ciMODULE_IMPORT_NS(PECI); 600