diff options
| author | Jinke Han <jinkehan@didiglobal.com> | 2026-09-08 15:37:42 +0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2026-09-17 09:48:42 +0200 |
| commit | a5f7a5bb3b7f28ba7e4fa246775b29a0e5537255 (patch) | |
| tree | 73fef824f9a846cf935869d0dbc5070ef6e2f741 /drivers/peci/controller/peci-aspeed.c | |
| download | linux-stable-a5f7a5bb3b7f28ba7e4fa246775b29a0e5537255.tar.gz linux-stable-a5f7a5bb3b7f28ba7e4fa246775b29a0e5537255.zip | |
x86/kprobes: Fix crash when probing CS CALL instructionsgrafted
When using eBPF to probe CS CALL instructions within a function,
a crash can be triggered.
The eBPF tool probes offset 257 of the __hrtimer_run_queues()
function:
<__hrtimer_run_queues+249>: nopl 0x0(%rax,%rax,1)
<__hrtimer_run_queues+254>: mov %r14,%rdi
<__hrtimer_run_queues+257>: cs call <__x86_indirect_thunk_r12>
<__hrtimer_run_queues+263>: mov %eax,%r12d
<__hrtimer_run_queues+266>: xchg %ax,%ax
<__hrtimer_run_queues+268>: mov %r13,%rdi
Which triggers this crash:
BUG: unable to handle page fault for address: 00000000000f41c9
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] SMP NOPTI
CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: P
RIP: 0010:__hrtimer_run_queues+0x106/0x230
Note that __hrtimer_run_queues+0x106 is __hrtimer_run_queues+262, which is
at the 6th byte of the above CS CALL instruction. Since the CS CALL
instruction occupies 6 bytes, the exception occurred in the middle of that
call instruction.
The root cause is that when using eBPF tools to probe in the middle of a
function, a kprobe with INT3 is used as the underlying implementation.
During single-step emulation of the original CALL instruction,
int3_emulate_call() assumes that the probed CALL instruction is 5 bytes
long. However, the actual CS-prefixed CALL instruction occupies 6 bytes,
so it constructs an incorrect exception return address. When the CPU
returns from the kprobe handler, the next instruction to be executed is at
the address of the last byte of that CS CALL instruction. Coincidentally,
starting from that address, the CPU fetches and decodes a completely
different instruction, which ultimately triggers a kernel crash.
Fix the issue by using the actual instruction length obtained from
the instruction decoder when constructing the exception return
address, rather than relying on the hardcoded CALL_INSN_SIZE macro.
[ mingo: Refined the changelog ]
Fixes: 6256e668b7af ("x86/kprobes: Use int3 instead of debug trap for single-step")
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Jinke Han <jinkehan@didiglobal.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://patch.msgid.link/20260908073742.GA10517@didi-ThinkCentre-M920t-N000
Diffstat (limited to 'drivers/peci/controller/peci-aspeed.c')
| -rw-r--r-- | drivers/peci/controller/peci-aspeed.c | 602 |
1 files changed, 602 insertions, 0 deletions
diff --git a/drivers/peci/controller/peci-aspeed.c b/drivers/peci/controller/peci-aspeed.c new file mode 100644 index 000000000..a0c99ecf7 --- /dev/null +++ b/drivers/peci/controller/peci-aspeed.c @@ -0,0 +1,602 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) 2012-2017 ASPEED Technology Inc. +// Copyright (c) 2018-2021 Intel Corporation + +#include <linux/unaligned.h> + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/jiffies.h> +#include <linux/math.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/peci.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +/* ASPEED PECI Registers */ +/* Control Register */ +#define ASPEED_PECI_CTRL 0x00 +#define ASPEED_PECI_CTRL_SAMPLING_MASK GENMASK(19, 16) +#define ASPEED_PECI_CTRL_RD_MODE_MASK GENMASK(13, 12) +#define ASPEED_PECI_CTRL_RD_MODE_DBG BIT(13) +#define ASPEED_PECI_CTRL_RD_MODE_COUNT BIT(12) +#define ASPEED_PECI_CTRL_CLK_SRC_HCLK BIT(11) +#define ASPEED_PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8) +#define ASPEED_PECI_CTRL_INVERT_OUT BIT(7) +#define ASPEED_PECI_CTRL_INVERT_IN BIT(6) +#define ASPEED_PECI_CTRL_BUS_CONTENTION_EN BIT(5) +#define ASPEED_PECI_CTRL_PECI_EN BIT(4) +#define ASPEED_PECI_CTRL_PECI_CLK_EN BIT(0) + +/* Timing Negotiation Register */ +#define ASPEED_PECI_TIMING_NEGOTIATION 0x04 +#define ASPEED_PECI_T_NEGO_MSG_MASK GENMASK(15, 8) +#define ASPEED_PECI_T_NEGO_ADDR_MASK GENMASK(7, 0) + +/* Command Register */ +#define ASPEED_PECI_CMD 0x08 +#define ASPEED_PECI_CMD_PIN_MONITORING BIT(31) +#define ASPEED_PECI_CMD_STS_MASK GENMASK(27, 24) +#define ASPEED_PECI_CMD_STS_ADDR_T_NEGO 0x3 +#define ASPEED_PECI_CMD_IDLE_MASK \ + (ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING) +#define ASPEED_PECI_CMD_FIRE BIT(0) + +/* Read/Write Length Register */ +#define ASPEED_PECI_RW_LENGTH 0x0c +#define ASPEED_PECI_AW_FCS_EN BIT(31) +#define ASPEED_PECI_RD_LEN_MASK GENMASK(23, 16) +#define ASPEED_PECI_WR_LEN_MASK GENMASK(15, 8) +#define ASPEED_PECI_TARGET_ADDR_MASK GENMASK(7, 0) + +/* Expected FCS Data Register */ +#define ASPEED_PECI_EXPECTED_FCS 0x10 +#define ASPEED_PECI_EXPECTED_RD_FCS_MASK GENMASK(23, 16) +#define ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK GENMASK(15, 8) +#define ASPEED_PECI_EXPECTED_WR_FCS_MASK GENMASK(7, 0) + +/* Captured FCS Data Register */ +#define ASPEED_PECI_CAPTURED_FCS 0x14 +#define ASPEED_PECI_CAPTURED_RD_FCS_MASK GENMASK(23, 16) +#define ASPEED_PECI_CAPTURED_WR_FCS_MASK GENMASK(7, 0) + +/* Interrupt Register */ +#define ASPEED_PECI_INT_CTRL 0x18 +#define ASPEED_PECI_TIMING_NEGO_SEL_MASK GENMASK(31, 30) +#define ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO 0 +#define ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO 1 +#define ASPEED_PECI_MESSAGE_NEGO 2 +#define ASPEED_PECI_INT_MASK GENMASK(4, 0) +#define ASPEED_PECI_INT_BUS_TIMEOUT BIT(4) +#define ASPEED_PECI_INT_BUS_CONTENTION BIT(3) +#define ASPEED_PECI_INT_WR_FCS_BAD BIT(2) +#define ASPEED_PECI_INT_WR_FCS_ABORT BIT(1) +#define ASPEED_PECI_INT_CMD_DONE BIT(0) + +/* Interrupt Status Register */ +#define ASPEED_PECI_INT_STS 0x1c +#define ASPEED_PECI_INT_TIMING_RESULT_MASK GENMASK(29, 16) + /* bits[4..0]: Same bit fields in the 'Interrupt Register' */ + +/* Rx/Tx Data Buffer Registers */ +#define ASPEED_PECI_WR_DATA0 0x20 +#define ASPEED_PECI_WR_DATA1 0x24 +#define ASPEED_PECI_WR_DATA2 0x28 +#define ASPEED_PECI_WR_DATA3 0x2c +#define ASPEED_PECI_RD_DATA0 0x30 +#define ASPEED_PECI_RD_DATA1 0x34 +#define ASPEED_PECI_RD_DATA2 0x38 +#define ASPEED_PECI_RD_DATA3 0x3c +#define ASPEED_PECI_WR_DATA4 0x40 +#define ASPEED_PECI_WR_DATA5 0x44 +#define ASPEED_PECI_WR_DATA6 0x48 +#define ASPEED_PECI_WR_DATA7 0x4c +#define ASPEED_PECI_RD_DATA4 0x50 +#define ASPEED_PECI_RD_DATA5 0x54 +#define ASPEED_PECI_RD_DATA6 0x58 +#define ASPEED_PECI_RD_DATA7 0x5c +#define ASPEED_PECI_DATA_BUF_SIZE_MAX 32 + +/* Timing Negotiation */ +#define ASPEED_PECI_CLK_FREQUENCY_MIN 2000 +#define ASPEED_PECI_CLK_FREQUENCY_DEFAULT 1000000 +#define ASPEED_PECI_CLK_FREQUENCY_MAX 2000000 +#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT 8 +/* Timeout */ +#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US (50 * USEC_PER_MSEC) +#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US (10 * USEC_PER_MSEC) +#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT 1000 +#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX 1000 + +#define ASPEED_PECI_CLK_DIV1(msg_timing) (4 * (msg_timing) + 1) +#define ASPEED_PECI_CLK_DIV2(clk_div_exp) BIT(clk_div_exp) +#define ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp) \ + (4 * ASPEED_PECI_CLK_DIV1(msg_timing) * ASPEED_PECI_CLK_DIV2(clk_div_exp)) + +struct aspeed_peci { + struct peci_controller *controller; + struct device *dev; + void __iomem *base; + struct reset_control *rst; + int irq; + spinlock_t lock; /* to sync completion status handling */ + struct completion xfer_complete; + struct clk *clk; + u32 clk_frequency; + u32 status; + u32 cmd_timeout_ms; +}; + +struct clk_aspeed_peci { + struct clk_hw hw; + struct aspeed_peci *aspeed_peci; +}; + +static void aspeed_peci_controller_enable(struct aspeed_peci *priv) +{ + u32 val = readl(priv->base + ASPEED_PECI_CTRL); + + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; + val |= ASPEED_PECI_CTRL_PECI_EN; + + writel(val, priv->base + ASPEED_PECI_CTRL); +} + +static void aspeed_peci_init_regs(struct aspeed_peci *priv) +{ + u32 val; + + /* Clear interrupts */ + writel(ASPEED_PECI_INT_MASK, priv->base + ASPEED_PECI_INT_STS); + + /* Set timing negotiation mode and enable interrupts */ + val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO); + val |= ASPEED_PECI_INT_MASK; + writel(val, priv->base + ASPEED_PECI_INT_CTRL); + + val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT); + writel(val, priv->base + ASPEED_PECI_CTRL); +} + +static int aspeed_peci_check_idle(struct aspeed_peci *priv) +{ + u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD); + int ret; + + /* + * Under normal circumstances, we expect to be idle here. + * In case there were any errors/timeouts that led to the situation + * where the hardware is not in idle state - we need to reset and + * reinitialize it to avoid potential controller hang. + */ + if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts)) { + ret = reset_control_assert(priv->rst); + if (ret) { + dev_err(priv->dev, "cannot assert reset control\n"); + return ret; + } + + ret = reset_control_deassert(priv->rst); + if (ret) { + dev_err(priv->dev, "cannot deassert reset control\n"); + return ret; + } + + aspeed_peci_init_regs(priv); + + ret = clk_set_rate(priv->clk, priv->clk_frequency); + if (ret < 0) { + dev_err(priv->dev, "cannot set clock frequency\n"); + return ret; + } + + aspeed_peci_controller_enable(priv); + } + + return readl_poll_timeout(priv->base + ASPEED_PECI_CMD, + cmd_sts, + !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK), + ASPEED_PECI_IDLE_CHECK_INTERVAL_US, + ASPEED_PECI_IDLE_CHECK_TIMEOUT_US); +} + +static int aspeed_peci_xfer(struct peci_controller *controller, + u8 addr, struct peci_request *req) +{ + struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent); + unsigned long timeout = msecs_to_jiffies(priv->cmd_timeout_ms); + u32 peci_head; + int ret, i; + + if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || + req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) + return -EINVAL; + + /* Check command sts and bus idle state */ + ret = aspeed_peci_check_idle(priv); + if (ret) + return ret; /* -ETIMEDOUT */ + + spin_lock_irq(&priv->lock); + reinit_completion(&priv->xfer_complete); + + peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | + FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | + FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); + + writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); + + for (i = 0; i < req->tx.len; i += 4) { + u32 reg = (i < 16 ? ASPEED_PECI_WR_DATA0 : ASPEED_PECI_WR_DATA4) + i % 16; + + writel(get_unaligned_le32(&req->tx.buf[i]), priv->base + reg); + } + +#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG) + dev_dbg(priv->dev, "HEAD : %#08x\n", peci_head); + print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req->tx.len); +#endif + + priv->status = 0; + writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); + spin_unlock_irq(&priv->lock); + + ret = wait_for_completion_interruptible_timeout(&priv->xfer_complete, timeout); + if (ret < 0) + return ret; + + if (ret == 0) { + dev_dbg(priv->dev, "timeout waiting for a response\n"); + return -ETIMEDOUT; + } + + spin_lock_irq(&priv->lock); + + if (priv->status != ASPEED_PECI_INT_CMD_DONE) { + spin_unlock_irq(&priv->lock); + dev_dbg(priv->dev, "no valid response, status: %#02x\n", priv->status); + return -EIO; + } + + spin_unlock_irq(&priv->lock); + + /* + * We need to use dword reads for register access, make sure that the + * buffer size is multiple of 4-bytes. + */ + BUILD_BUG_ON(PECI_REQUEST_MAX_BUF_SIZE % 4); + + for (i = 0; i < req->rx.len; i += 4) { + u32 reg = (i < 16 ? ASPEED_PECI_RD_DATA0 : ASPEED_PECI_RD_DATA4) + i % 16; + u32 rx_data = readl(priv->base + reg); + + put_unaligned_le32(rx_data, &req->rx.buf[i]); + } + +#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG) + print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req->rx.len); +#endif + return 0; +} + +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) +{ + struct aspeed_peci *priv = arg; + u32 status; + + spin_lock(&priv->lock); + status = readl(priv->base + ASPEED_PECI_INT_STS); + writel(status, priv->base + ASPEED_PECI_INT_STS); + priv->status |= (status & ASPEED_PECI_INT_MASK); + + /* + * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE bit + * set even in an error case. + */ + if (status & ASPEED_PECI_INT_CMD_DONE) + complete(&priv->xfer_complete); + + writel(0, priv->base + ASPEED_PECI_CMD); + + spin_unlock(&priv->lock); + + return IRQ_HANDLED; +} + +static void clk_aspeed_peci_find_div_values(unsigned long rate, int *msg_timing, int *clk_div_exp) +{ + unsigned long best_diff = ~0ul, diff; + int msg_timing_temp, clk_div_exp_temp, i, j; + + for (i = 1; i <= 255; i++) + for (j = 0; j < 8; j++) { + diff = abs(rate - ASPEED_PECI_CLK_DIV1(i) * ASPEED_PECI_CLK_DIV2(j)); + if (diff < best_diff) { + msg_timing_temp = i; + clk_div_exp_temp = j; + best_diff = diff; + } + } + + *msg_timing = msg_timing_temp; + *clk_div_exp = clk_div_exp_temp; +} + +static int clk_aspeed_peci_get_div(unsigned long rate, const unsigned long *prate) +{ + unsigned long this_rate = *prate / (4 * rate); + int msg_timing, clk_div_exp; + + clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp); + + return ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp); +} + +static int clk_aspeed_peci_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long prate) +{ + struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw); + struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci; + unsigned long this_rate = prate / (4 * rate); + int clk_div_exp, msg_timing; + u32 val; + + clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp); + + val = readl(aspeed_peci->base + ASPEED_PECI_CTRL); + val &= ~ASPEED_PECI_CTRL_CLK_DIV_MASK; + val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, clk_div_exp); + writel(val, aspeed_peci->base + ASPEED_PECI_CTRL); + + val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, msg_timing); + val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, msg_timing); + writel(val, aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION); + + return 0; +} + +static int clk_aspeed_peci_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + int div = clk_aspeed_peci_get_div(req->rate, &req->best_parent_rate); + + req->rate = DIV_ROUND_UP_ULL(req->best_parent_rate, div); + + return 0; +} + +static unsigned long clk_aspeed_peci_recalc_rate(struct clk_hw *hw, unsigned long prate) +{ + struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw); + struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci; + int div, msg_timing, addr_timing, clk_div_exp; + u32 reg; + + reg = readl(aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION); + msg_timing = FIELD_GET(ASPEED_PECI_T_NEGO_MSG_MASK, reg); + addr_timing = FIELD_GET(ASPEED_PECI_T_NEGO_ADDR_MASK, reg); + + if (msg_timing != addr_timing) + return 0; + + reg = readl(aspeed_peci->base + ASPEED_PECI_CTRL); + clk_div_exp = FIELD_GET(ASPEED_PECI_CTRL_CLK_DIV_MASK, reg); + + div = ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp); + + return DIV_ROUND_UP_ULL(prate, div); +} + +static const struct clk_ops clk_aspeed_peci_ops = { + .set_rate = clk_aspeed_peci_set_rate, + .determine_rate = clk_aspeed_peci_determine_rate, + .recalc_rate = clk_aspeed_peci_recalc_rate, +}; + +/* + * PECI HW contains a clock divider which is a combination of: + * div0: 4 (fixed divider) + * div1: x + 1 + * div2: 1 << y + * In other words, out_clk = in_clk / (div0 * div1 * div2) + * The resulting frequency is used by PECI Controller to drive the PECI bus to + * negotiate optimal transfer rate. + */ +static struct clk *devm_aspeed_peci_register_clk_div(struct device *dev, struct clk *parent, + struct aspeed_peci *priv) +{ + struct clk_aspeed_peci *peci_clk; + struct clk_init_data init; + const char *parent_name; + char name[32]; + int ret; + + snprintf(name, sizeof(name), "%s_div", dev_name(dev)); + + parent_name = __clk_get_name(parent); + + init.ops = &clk_aspeed_peci_ops; + init.name = name; + init.parent_names = (const char* []) { parent_name }; + init.num_parents = 1; + init.flags = 0; + + peci_clk = devm_kzalloc(dev, sizeof(struct clk_aspeed_peci), GFP_KERNEL); + if (!peci_clk) + return ERR_PTR(-ENOMEM); + + peci_clk->hw.init = &init; + peci_clk->aspeed_peci = priv; + + ret = devm_clk_hw_register(dev, &peci_clk->hw); + if (ret) + return ERR_PTR(ret); + + return peci_clk->hw.clk; +} + +static void aspeed_peci_property_sanitize(struct device *dev, const char *propname, + u32 min, u32 max, u32 default_val, u32 *propval) +{ + u32 val; + int ret; + + ret = device_property_read_u32(dev, propname, &val); + if (ret) { + val = default_val; + } else if (val > max || val < min) { + dev_warn(dev, "invalid %s: %u, falling back to: %u\n", + propname, val, default_val); + + val = default_val; + } + + *propval = val; +} + +static void aspeed_peci_property_setup(struct aspeed_peci *priv) +{ + aspeed_peci_property_sanitize(priv->dev, "clock-frequency", + ASPEED_PECI_CLK_FREQUENCY_MIN, ASPEED_PECI_CLK_FREQUENCY_MAX, + ASPEED_PECI_CLK_FREQUENCY_DEFAULT, &priv->clk_frequency); + aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms", + 1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX, + ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, &priv->cmd_timeout_ms); +} + +static const struct peci_controller_ops aspeed_ops = { + .xfer = aspeed_peci_xfer, +}; + +static void aspeed_peci_reset_control_release(void *data) +{ + reset_control_assert(data); +} + +static int devm_aspeed_peci_reset_control_deassert(struct device *dev, struct reset_control *rst) +{ + int ret; + + ret = reset_control_deassert(rst); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, aspeed_peci_reset_control_release, rst); +} + +static void aspeed_peci_clk_release(void *data) +{ + clk_disable_unprepare(data); +} + +static int devm_aspeed_peci_clk_enable(struct device *dev, struct clk *clk) +{ + int ret; + + ret = clk_prepare_enable(clk); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk); +} + +static int aspeed_peci_probe(struct platform_device *pdev) +{ + struct peci_controller *controller; + struct aspeed_peci *priv; + struct clk *ref_clk; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = &pdev->dev; + dev_set_drvdata(priv->dev, priv); + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + priv->irq = platform_get_irq(pdev, 0); + if (priv->irq < 0) + return priv->irq; + + ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler, + 0, "peci-aspeed", priv); + if (ret) + return ret; + + init_completion(&priv->xfer_complete); + spin_lock_init(&priv->lock); + + priv->rst = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(priv->rst)) + return dev_err_probe(priv->dev, PTR_ERR(priv->rst), + "failed to get reset control\n"); + + ret = devm_aspeed_peci_reset_control_deassert(priv->dev, priv->rst); + if (ret) + return dev_err_probe(priv->dev, ret, "cannot deassert reset control\n"); + + aspeed_peci_property_setup(priv); + + aspeed_peci_init_regs(priv); + + ref_clk = devm_clk_get(priv->dev, NULL); + if (IS_ERR(ref_clk)) + return dev_err_probe(priv->dev, PTR_ERR(ref_clk), "failed to get ref clock\n"); + + priv->clk = devm_aspeed_peci_register_clk_div(priv->dev, ref_clk, priv); + if (IS_ERR(priv->clk)) + return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "cannot register clock\n"); + + ret = clk_set_rate(priv->clk, priv->clk_frequency); + if (ret < 0) + return dev_err_probe(priv->dev, ret, "cannot set clock frequency\n"); + + ret = devm_aspeed_peci_clk_enable(priv->dev, priv->clk); + if (ret) + return dev_err_probe(priv->dev, ret, "failed to enable clock\n"); + + aspeed_peci_controller_enable(priv); + + controller = devm_peci_controller_add(priv->dev, &aspeed_ops); + if (IS_ERR(controller)) + return dev_err_probe(priv->dev, PTR_ERR(controller), + "failed to add aspeed peci controller\n"); + + priv->controller = controller; + + return 0; +} + +static const struct of_device_id aspeed_peci_of_table[] = { + { .compatible = "aspeed,ast2400-peci", }, + { .compatible = "aspeed,ast2500-peci", }, + { .compatible = "aspeed,ast2600-peci", }, + { } +}; +MODULE_DEVICE_TABLE(of, aspeed_peci_of_table); + +static struct platform_driver aspeed_peci_driver = { + .probe = aspeed_peci_probe, + .driver = { + .name = "peci-aspeed", + .of_match_table = aspeed_peci_of_table, + }, +}; +module_platform_driver(aspeed_peci_driver); + +MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>"); +MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>"); +MODULE_DESCRIPTION("ASPEED PECI driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS("PECI"); |
