[PATCH v3 3/3] soc: aspeed: lpc-pcc: Add PCC controller support

Kevin Chen posted 3 patches 11 months ago
There is a newer version of this series
[PATCH v3 3/3] soc: aspeed: lpc-pcc: Add PCC controller support
Posted by Kevin Chen 11 months ago
Add LPC PCC controller driver to support POST code capture.

Signed-off-by: Kevin Chen <kevin_chen@aspeedtech.com>
---
 drivers/misc/Kconfig          |  10 +
 drivers/misc/Makefile         |   1 +
 drivers/misc/aspeed-lpc-pcc.c | 440 ++++++++++++++++++++++++++++++++++
 3 files changed, 451 insertions(+)
 create mode 100644 drivers/misc/aspeed-lpc-pcc.c

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 56bc72c7ce4a..35c1d2e0c271 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -50,6 +50,16 @@ config AD525X_DPOT_SPI
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad525x_dpot-spi.
 
+config ASPEED_LPC_PCC
+	tristate "Aspeed Post Code Capture support"
+	select REGMAP
+	select MFD_SYSCON
+	default ARCH_ASPEED
+	help
+	  Provides a driver to control the LPC PCC interface,
+	  allowing the BMC to capture post code written by the
+	  the host to an arbitrary LPC I/O port.
+
 config DUMMY_IRQ
 	tristate "Dummy IRQ handler"
 	help
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 545aad06d088..4762da7804bf 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_IBMVMC)		+= ibmvmc.o
 obj-$(CONFIG_AD525X_DPOT)	+= ad525x_dpot.o
 obj-$(CONFIG_AD525X_DPOT_I2C)	+= ad525x_dpot-i2c.o
 obj-$(CONFIG_AD525X_DPOT_SPI)	+= ad525x_dpot-spi.o
+obj-$(CONFIG_ASPEED_LPC_PCC)	+= aspeed-lpc-pcc.o
 obj-$(CONFIG_ATMEL_SSC)		+= atmel-ssc.o
 obj-$(CONFIG_DUMMY_IRQ)		+= dummy-irq.o
 obj-$(CONFIG_ICS932S401)	+= ics932s401.o
diff --git a/drivers/misc/aspeed-lpc-pcc.c b/drivers/misc/aspeed-lpc-pcc.c
new file mode 100644
index 000000000000..9ed4b453d199
--- /dev/null
+++ b/drivers/misc/aspeed-lpc-pcc.c
@@ -0,0 +1,440 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) ASPEED Technology Inc.
+ */
+#include <linux/bitops.h>
+#include <linux/bitfield.h>
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/kfifo.h>
+#include <linux/mfd/syscon.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/regmap.h>
+#include <linux/dma-mapping.h>
+#include <linux/sizes.h>
+
+#define DEVICE_NAME "aspeed-lpc-pcc"
+
+static DEFINE_IDA(aspeed_pcc_ida);
+
+#define HICR5	0x80
+#define HICR5_EN_SNP0W			BIT(0)
+#define HICR5_EN_SNP1W			BIT(2)
+#define HICR6	0x084
+#define   HICR6_EN2BMODE		BIT(19)
+#define SNPWADR	0x090
+#define PCCR6	0x0c4
+#define   PCCR6_DMA_CUR_ADDR		GENMASK(27, 0)
+#define PCCR4	0x0d0
+#define   PCCR4_DMA_ADDRL_MASK		GENMASK(31, 0)
+#define   PCCR4_DMA_ADDRL_SHIFT		0
+#define PCCR5	0x0d4
+#define   PCCR5_DMA_ADDRH_MASK		GENMASK(27, 24)
+#define   PCCR5_DMA_ADDRH_SHIFT		24
+#define   PCCR5_DMA_LEN_MASK		GENMASK(23, 0)
+#define   PCCR5_DMA_LEN_SHIFT		0
+#define HICRB	0x100
+#define   HICRB_ENSNP0D			BIT(14)
+#define   HICRB_ENSNP1D			BIT(15)
+#define PCCR0	0x130
+#define   PCCR0_EN_DMA_INT		BIT(31)
+#define   PCCR0_EN_DMA_MODE		BIT(14)
+#define   PCCR0_ADDR_SEL_MASK		GENMASK(13, 12)
+#define   PCCR0_ADDR_SEL_SHIFT		12
+#define   PCCR0_RX_TRIG_LVL_MASK	GENMASK(10, 8)
+#define   PCCR0_RX_TRIG_LVL_SHIFT	8
+#define   PCCR0_CLR_RX_FIFO		BIT(7)
+#define   PCCR0_MODE_SEL_MASK		GENMASK(5, 4)
+#define   PCCR0_MODE_SEL_SHIFT		4
+#define   PCCR0_EN_RX_TMOUT_INT		BIT(2)
+#define   PCCR0_EN_RX_AVAIL_INT		BIT(1)
+#define   PCCR0_EN			BIT(0)
+#define PCCR1	0x134
+#define   PCCR1_BASE_ADDR_MASK		GENMASK(15, 0)
+#define   PCCR1_BASE_ADDR_SHIFT		0
+#define   PCCR1_DONT_CARE_BITS_MASK	GENMASK(21, 16)
+#define   PCCR1_DONT_CARE_BITS_SHIFT	16
+#define PCCR2	0x138
+#define   PCCR2_INT_STATUS_PATTERN_B	BIT(16)
+#define   PCCR2_INT_STATUS_PATTERN_A	BIT(8)
+#define   PCCR2_INT_STATUS_DMA_DONE	BIT(4)
+#define   PCCR2_INT_STATUS_DATA_RDY	PCCR2_INT_STATUS_DMA_DONE
+#define   PCCR2_INT_STATUS_RX_OVER	BIT(3)
+#define   PCCR2_INT_STATUS_RX_TMOUT	BIT(2)
+#define   PCCR2_INT_STATUS_RX_AVAIL	BIT(1)
+#define PCCR3	0x13c
+#define   PCCR3_FIFO_DATA_MASK		GENMASK(7, 0)
+
+#define PCC_DMA_BUFSZ	(256 * SZ_1K)
+
+enum pcc_fifo_threshold {
+	PCC_FIFO_THR_1_BYTE,
+	PCC_FIFO_THR_1_EIGHTH,
+	PCC_FIFO_THR_2_EIGHTH,
+	PCC_FIFO_THR_3_EIGHTH,
+	PCC_FIFO_THR_4_EIGHTH,
+	PCC_FIFO_THR_5_EIGHTH,
+	PCC_FIFO_THR_6_EIGHTH,
+	PCC_FIFO_THR_7_EIGHTH,
+	PCC_FIFO_THR_8_EIGHTH,
+};
+
+enum pcc_record_mode {
+	PCC_REC_1B,
+	PCC_REC_2B,
+	PCC_REC_4B,
+	PCC_REC_FULL,
+};
+
+enum pcc_port_hbits_select {
+	PCC_PORT_HBITS_SEL_NONE,
+	PCC_PORT_HBITS_SEL_45,
+	PCC_PORT_HBITS_SEL_67,
+	PCC_PORT_HBITS_SEL_89,
+};
+
+struct aspeed_pcc_dma {
+	uint32_t rptr;
+	uint8_t *virt;
+	dma_addr_t addr;
+	uint32_t size;
+};
+
+struct aspeed_pcc_ctrl {
+	struct device *dev;
+	struct regmap *regmap;
+	int irq;
+	uint32_t port;
+	struct aspeed_pcc_dma dma;
+	struct kfifo fifo;
+	wait_queue_head_t wq;
+	struct miscdevice mdev;
+	int mdev_id;
+};
+
+static inline bool is_valid_rec_mode(uint32_t mode)
+{
+	return (mode > PCC_REC_FULL) ? false : true;
+}
+
+static inline bool is_valid_high_bits_select(uint32_t sel)
+{
+	return (sel > PCC_PORT_HBITS_SEL_89) ? false : true;
+}
+
+static ssize_t aspeed_pcc_file_read(struct file *file, char __user *buffer,
+				    size_t count, loff_t *ppos)
+{
+	int rc;
+	unsigned int copied;
+	struct aspeed_pcc_ctrl *pcc = container_of(file->private_data,
+					      struct aspeed_pcc_ctrl,
+					      mdev);
+
+	if (kfifo_is_empty(&pcc->fifo)) {
+		if (file->f_flags & O_NONBLOCK)
+			return -EAGAIN;
+
+		rc = wait_event_interruptible(pcc->wq,
+					      !kfifo_is_empty(&pcc->fifo));
+		if (rc == -ERESTARTSYS)
+			return -EINTR;
+	}
+
+	rc = kfifo_to_user(&pcc->fifo, buffer, count, &copied);
+
+	return rc ? rc : copied;
+}
+
+static __poll_t aspeed_pcc_file_poll(struct file *file,
+				     struct poll_table_struct *pt)
+{
+	struct aspeed_pcc_ctrl *pcc = container_of(file->private_data,
+					      struct aspeed_pcc_ctrl,
+					      mdev);
+
+	poll_wait(file, &pcc->wq, pt);
+
+	return !kfifo_is_empty(&pcc->fifo) ? POLLIN : 0;
+}
+
+static const struct file_operations pcc_fops = {
+	.owner = THIS_MODULE,
+	.read = aspeed_pcc_file_read,
+	.poll = aspeed_pcc_file_poll,
+};
+
+static irqreturn_t aspeed_pcc_dma_isr(int irq, void *arg)
+{
+	uint32_t reg, rptr, wptr;
+	struct aspeed_pcc_ctrl *pcc = (struct aspeed_pcc_ctrl *)arg;
+	struct kfifo *fifo = &pcc->fifo;
+
+	regmap_write_bits(pcc->regmap, PCCR2, PCCR2_INT_STATUS_DMA_DONE, PCCR2_INT_STATUS_DMA_DONE);
+
+	regmap_read(pcc->regmap, PCCR6, &reg);
+	wptr = (reg & PCCR6_DMA_CUR_ADDR) - (pcc->dma.addr & PCCR6_DMA_CUR_ADDR);
+	rptr = pcc->dma.rptr;
+
+	do {
+		if (kfifo_is_full(fifo))
+			kfifo_skip(fifo);
+
+		kfifo_put(fifo, pcc->dma.virt[rptr]);
+
+		rptr = (rptr + 1) % pcc->dma.size;
+	} while (rptr != wptr);
+
+	pcc->dma.rptr = rptr;
+
+	wake_up_interruptible(&pcc->wq);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t aspeed_pcc_isr(int irq, void *arg)
+{
+	uint32_t sts;
+	struct aspeed_pcc_ctrl *pcc = (struct aspeed_pcc_ctrl *)arg;
+
+	regmap_read(pcc->regmap, PCCR2, &sts);
+
+	if (!(sts & (PCCR2_INT_STATUS_RX_TMOUT |
+		     PCCR2_INT_STATUS_RX_AVAIL |
+		     PCCR2_INT_STATUS_DMA_DONE)))
+		return IRQ_NONE;
+
+	return aspeed_pcc_dma_isr(irq, arg);
+}
+
+/*
+ * A2600-15 AP note
+ *
+ * SW workaround to prevent generating Non-Fatal-Error (NFE)
+ * eSPI response when PCC is used for port I/O byte snooping
+ * over eSPI.
+ */
+static int aspeed_a2600_15(struct aspeed_pcc_ctrl *pcc, struct device *dev)
+{
+	u32 hicr5_en, hicrb_en;
+
+	/* abort if snoop is enabled */
+	regmap_read(pcc->regmap, HICR5, &hicr5_en);
+	if (hicr5_en & (HICR5_EN_SNP0W | HICR5_EN_SNP1W)) {
+		dev_err(dev, "A2600-15 should be applied with snoop disabled\n");
+		return -EPERM;
+	}
+
+	/* set SNPWADR of snoop device */
+	regmap_write(pcc->regmap, SNPWADR, pcc->port | ((pcc->port + 2) << 16));
+
+	/* set HICRB[15:14]=11b to enable ACCEPT response for SNPWADR */
+	hicrb_en = HICRB_ENSNP0D | HICRB_ENSNP1D;
+	regmap_update_bits(pcc->regmap, HICRB, hicrb_en, hicrb_en);
+
+	/* set HICR6[19] to extend SNPWADR to 2x range */
+	regmap_update_bits(pcc->regmap, HICR6, HICR6_EN2BMODE, HICR6_EN2BMODE);
+
+	return 0;
+}
+
+static int aspeed_pcc_enable(struct aspeed_pcc_ctrl *pcc, struct device *dev)
+{
+	int rc;
+
+	rc = aspeed_a2600_15(pcc, dev);
+	if (rc)
+		return rc;
+
+	/* record mode: Set 2-Byte mode. */
+	regmap_update_bits(pcc->regmap, PCCR0,
+			   PCCR0_MODE_SEL_MASK,
+			   PCC_REC_2B << PCCR0_MODE_SEL_SHIFT);
+
+	/* port address */
+	regmap_update_bits(pcc->regmap, PCCR1,
+			   PCCR1_BASE_ADDR_MASK,
+			   pcc->port << PCCR1_BASE_ADDR_SHIFT);
+
+	/* Set address high bits selection to 0b01 for address bit[5:4] */
+	regmap_update_bits(pcc->regmap, PCCR0,
+			   PCCR0_ADDR_SEL_MASK,
+			   PCC_PORT_HBITS_SEL_45 << PCCR0_ADDR_SEL_SHIFT);
+
+	/* Set LPC don't care address to 0x3 for port 80~83h */
+	regmap_update_bits(pcc->regmap, PCCR1,
+			   PCCR1_DONT_CARE_BITS_MASK,
+			   0x3 << PCCR1_DONT_CARE_BITS_SHIFT);
+
+	/* set DMA ring buffer size and enable interrupts */
+	regmap_write(pcc->regmap, PCCR4, pcc->dma.addr & 0xffffffff);
+#ifdef CONFIG_ARM64
+	regmap_update_bits(pcc->regmap, PCCR5, PCCR5_DMA_ADDRH_MASK,
+			   (pcc->dma.addr >> 32) << PCCR5_DMA_ADDRH_SHIFT);
+#endif
+	regmap_update_bits(pcc->regmap, PCCR5, PCCR5_DMA_LEN_MASK,
+			   (pcc->dma.size / 4) << PCCR5_DMA_LEN_SHIFT);
+	regmap_update_bits(pcc->regmap, PCCR0,
+			   PCCR0_EN_DMA_INT | PCCR0_EN_DMA_MODE,
+			   PCCR0_EN_DMA_INT | PCCR0_EN_DMA_MODE);
+
+	regmap_update_bits(pcc->regmap, PCCR0, PCCR0_EN, PCCR0_EN);
+
+	return 0;
+}
+
+static int aspeed_pcc_disable(struct aspeed_pcc_ctrl *pcc)
+{
+	/* Disable PCC and DMA Mode for safety */
+	regmap_update_bits(pcc->regmap, PCCR0, PCCR0_EN |  PCCR0_EN_DMA_MODE, 0);
+
+	/* Clear Rx FIFO. */
+	regmap_update_bits(pcc->regmap, PCCR0, PCCR0_CLR_RX_FIFO, 1);
+
+	/* Clear All interrupts status. */
+	regmap_write(pcc->regmap, PCCR2,
+		     PCCR2_INT_STATUS_RX_OVER | PCCR2_INT_STATUS_DMA_DONE |
+		     PCCR2_INT_STATUS_PATTERN_A | PCCR2_INT_STATUS_PATTERN_B);
+
+	return 0;
+}
+
+static int aspeed_pcc_probe(struct platform_device *pdev)
+{
+	int rc;
+	struct aspeed_pcc_ctrl *pcc;
+	struct device *dev = &pdev->dev;
+	uint32_t fifo_size = PAGE_SIZE;
+
+	pcc = devm_kzalloc(dev, sizeof(*pcc), GFP_KERNEL);
+	if (!pcc)
+		return -ENOMEM;
+
+	pcc->regmap = syscon_node_to_regmap(dev->parent->of_node);
+	if (IS_ERR(pcc->regmap)) {
+		dev_err(dev, "Couldn't get regmap\n");
+		return -ENODEV;
+	}
+
+	rc = of_property_read_u32(dev->of_node, "pcc-ports", &pcc->port);
+	if (rc) {
+		dev_err(dev, "no pcc ports configured\n");
+		return -ENODEV;
+	}
+
+	rc = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
+	if (rc) {
+		dev_err(dev, "cannot set 64-bits DMA mask\n");
+		return rc;
+	}
+
+	pcc->dma.size = PCC_DMA_BUFSZ;
+	pcc->dma.virt = dmam_alloc_coherent(dev,
+					    pcc->dma.size,
+					    &pcc->dma.addr,
+					    GFP_KERNEL);
+	if (!pcc->dma.virt) {
+		dev_err(dev, "cannot allocate DMA buffer\n");
+		return -ENOMEM;
+	}
+
+	fifo_size = roundup(pcc->dma.size, PAGE_SIZE);
+	rc = kfifo_alloc(&pcc->fifo, fifo_size, GFP_KERNEL);
+	if (rc) {
+		return -ENOMEM;
+	}
+
+	/* Disable PCC to clean up DMA buffer before request IRQ. */
+	rc = aspeed_pcc_disable(pcc);
+	if (rc) {
+		dev_err(dev, "Couldn't disable PCC\n");
+		goto err_free_kfifo;
+	}
+
+	pcc->irq = platform_get_irq(pdev, 0);
+	if (pcc->irq < 0) {
+		rc = pcc->irq;
+		goto err_free_kfifo;
+	}
+
+	rc = devm_request_irq(dev, pcc->irq, aspeed_pcc_isr, 0, DEVICE_NAME, pcc);
+	if (rc < 0) {
+		dev_err(dev, "Couldn't request IRQ %d\n", pcc->irq);
+		goto err_free_kfifo;
+	}
+
+	init_waitqueue_head(&pcc->wq);
+
+	pcc->mdev_id = ida_alloc(&aspeed_pcc_ida, GFP_KERNEL);
+	if (pcc->mdev_id < 0) {
+		dev_err(dev, "Couldn't allocate ID\n");
+		goto err_free_kfifo;
+	}
+
+	pcc->mdev.parent = dev;
+	pcc->mdev.minor = MISC_DYNAMIC_MINOR;
+	pcc->mdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s%d", DEVICE_NAME,
+					pcc->mdev_id);
+	pcc->mdev.fops = &pcc_fops;
+	rc = misc_register(&pcc->mdev);
+	if (rc) {
+		dev_err(dev, "Couldn't register misc device\n");
+		goto err_free_ida;
+	}
+
+	rc = aspeed_pcc_enable(pcc, dev);
+	if (rc) {
+		dev_err(dev, "Couldn't enable PCC\n");
+		goto err_dereg_mdev;
+	}
+
+	dev_set_drvdata(dev, pcc);
+
+	return 0;
+
+err_dereg_mdev:
+	misc_deregister(&pcc->mdev);
+
+err_free_ida:
+	ida_free(&aspeed_pcc_ida, pcc->mdev_id);
+
+err_free_kfifo:
+	kfifo_free(&pcc->fifo);
+
+	return rc;
+}
+
+static void aspeed_pcc_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct aspeed_pcc_ctrl *pcc = dev_get_drvdata(dev);
+
+	kfifo_free(&pcc->fifo);
+	ida_free(&aspeed_pcc_ida, pcc->mdev_id);
+	misc_deregister(&pcc->mdev);
+}
+
+static const struct of_device_id aspeed_pcc_table[] = {
+	{ .compatible = "aspeed,ast2600-lpc-pcc" },
+};
+
+static struct platform_driver aspeed_pcc_driver = {
+	.driver = {
+		.name = "aspeed-pcc",
+		.of_match_table = aspeed_pcc_table,
+	},
+	.probe = aspeed_pcc_probe,
+	.remove = aspeed_pcc_remove,
+};
+
+module_platform_driver(aspeed_pcc_driver);
+
+MODULE_AUTHOR("Chia-Wei Wang <chiawei_wang@aspeedtech.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Driver for Aspeed Post Code Capture");
-- 
2.34.1
Re: [PATCH v3 3/3] soc: aspeed: lpc-pcc: Add PCC controller support
Posted by kernel test robot 11 months ago
Hi Kevin,

kernel test robot noticed the following build errors:

[auto build test ERROR on char-misc/char-misc-testing]
[also build test ERROR on char-misc/char-misc-next char-misc/char-misc-linus lee-leds/for-leds-next lee-mfd/for-mfd-next robh/for-next lee-mfd/for-mfd-fixes linus/master v6.14-rc6 next-20250314]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Kevin-Chen/dt-binding-aspeed-Add-LPC-PCC-controller/20250310-195011
base:   char-misc/char-misc-testing
patch link:    https://lore.kernel.org/r/20250310114839.3098148-4-kevin_chen%40aspeedtech.com
patch subject: [PATCH v3 3/3] soc: aspeed: lpc-pcc: Add PCC controller support
config: s390-randconfig-002-20250316 (https://download.01.org/0day-ci/archive/20250316/202503160530.EkUNSrkh-lkp@intel.com/config)
compiler: clang version 16.0.6 (https://github.com/llvm/llvm-project 7cbf1a2591520c2491aa35339f227775f4d3adf6)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250316/202503160530.EkUNSrkh-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202503160530.EkUNSrkh-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/mfd/syscon.c:157:2: error: call to undeclared function 'iounmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
           iounmap(base);
           ^
   arch/s390/include/asm/io.h:31:17: note: expanded from macro 'iounmap'
   #define iounmap iounmap
                   ^
   1 error generated.

Kconfig warnings: (for reference only)
   WARNING: unmet direct dependencies detected for MFD_SYSCON
   Depends on [n]: HAS_IOMEM [=n]
   Selected by [y]:
   - ASPEED_LPC_PCC [=y]


vim +/iounmap +157 drivers/mfd/syscon.c

87d687301f38072 Dong Aisheng        2012-09-05   39  
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05   40  static struct syscon *of_syscon_register(struct device_node *np, bool check_res)
87d687301f38072 Dong Aisheng        2012-09-05   41  {
a00406b71c5f08f Fabrice Gasnier     2018-12-12   42  	struct clk *clk;
bdb0066df96e74a Pankaj Dubey        2014-09-30   43  	struct regmap *regmap;
bdb0066df96e74a Pankaj Dubey        2014-09-30   44  	void __iomem *base;
db2fb60cd35d2d0 Damien Riegel       2015-11-30   45  	u32 reg_io_width;
bdb0066df96e74a Pankaj Dubey        2014-09-30   46  	int ret;
bdb0066df96e74a Pankaj Dubey        2014-09-30   47  	struct regmap_config syscon_config = syscon_regmap_config;
ca668f0edfae654 Philipp Zabel       2016-01-29   48  	struct resource res;
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05   49  	struct reset_control *reset;
bdb0066df96e74a Pankaj Dubey        2014-09-30   50  
805f7aaf7fee14a Rob Herring (Arm    2024-12-17   51) 	WARN_ON(!mutex_is_locked(&syscon_list_lock));
805f7aaf7fee14a Rob Herring (Arm    2024-12-17   52) 
82f898f47112bc7 Krzysztof Kozlowski 2024-07-07   53  	struct syscon *syscon __free(kfree) = kzalloc(sizeof(*syscon), GFP_KERNEL);
bdb0066df96e74a Pankaj Dubey        2014-09-30   54  	if (!syscon)
bdb0066df96e74a Pankaj Dubey        2014-09-30   55  		return ERR_PTR(-ENOMEM);
bdb0066df96e74a Pankaj Dubey        2014-09-30   56  
82f898f47112bc7 Krzysztof Kozlowski 2024-07-07   57  	if (of_address_to_resource(np, 0, &res))
82f898f47112bc7 Krzysztof Kozlowski 2024-07-07   58  		return ERR_PTR(-ENOMEM);
ca668f0edfae654 Philipp Zabel       2016-01-29   59  
452d07413954ef3 Hector Martin       2021-08-23   60  	base = of_iomap(np, 0);
82f898f47112bc7 Krzysztof Kozlowski 2024-07-07   61  	if (!base)
82f898f47112bc7 Krzysztof Kozlowski 2024-07-07   62  		return ERR_PTR(-ENOMEM);
bdb0066df96e74a Pankaj Dubey        2014-09-30   63  
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   64  	/* Parse the device's DT node for an endianness specification */
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   65  	if (of_property_read_bool(np, "big-endian"))
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   66  		syscon_config.val_format_endian = REGMAP_ENDIAN_BIG;
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   67  	else if (of_property_read_bool(np, "little-endian"))
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   68  		syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   69  	else if (of_property_read_bool(np, "native-endian"))
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   70  		syscon_config.val_format_endian = REGMAP_ENDIAN_NATIVE;
ca4582c286aa446 Jason A. Donenfeld  2022-10-08   71  
db2fb60cd35d2d0 Damien Riegel       2015-11-30   72  	/*
db2fb60cd35d2d0 Damien Riegel       2015-11-30   73  	 * search for reg-io-width property in DT. If it is not provided,
db2fb60cd35d2d0 Damien Riegel       2015-11-30   74  	 * default to 4 bytes. regmap_init_mmio will return an error if values
db2fb60cd35d2d0 Damien Riegel       2015-11-30   75  	 * are invalid so there is no need to check them here.
db2fb60cd35d2d0 Damien Riegel       2015-11-30   76  	 */
db2fb60cd35d2d0 Damien Riegel       2015-11-30   77  	ret = of_property_read_u32(np, "reg-io-width", &reg_io_width);
db2fb60cd35d2d0 Damien Riegel       2015-11-30   78  	if (ret)
db2fb60cd35d2d0 Damien Riegel       2015-11-30   79  		reg_io_width = 4;
db2fb60cd35d2d0 Damien Riegel       2015-11-30   80  
3bafc09e779710a Baolin Wang         2017-12-25   81  	ret = of_hwspin_lock_get_id(np, 0);
3bafc09e779710a Baolin Wang         2017-12-25   82  	if (ret > 0 || (IS_ENABLED(CONFIG_HWSPINLOCK) && ret == 0)) {
3bafc09e779710a Baolin Wang         2017-12-25   83  		syscon_config.use_hwlock = true;
3bafc09e779710a Baolin Wang         2017-12-25   84  		syscon_config.hwlock_id = ret;
3bafc09e779710a Baolin Wang         2017-12-25   85  		syscon_config.hwlock_mode = HWLOCK_IRQSTATE;
3bafc09e779710a Baolin Wang         2017-12-25   86  	} else if (ret < 0) {
3bafc09e779710a Baolin Wang         2017-12-25   87  		switch (ret) {
3bafc09e779710a Baolin Wang         2017-12-25   88  		case -ENOENT:
3bafc09e779710a Baolin Wang         2017-12-25   89  			/* Ignore missing hwlock, it's optional. */
3bafc09e779710a Baolin Wang         2017-12-25   90  			break;
3bafc09e779710a Baolin Wang         2017-12-25   91  		default:
3bafc09e779710a Baolin Wang         2017-12-25   92  			pr_err("Failed to retrieve valid hwlock: %d\n", ret);
df561f6688fef77 Gustavo A. R. Silva 2020-08-23   93  			fallthrough;
3bafc09e779710a Baolin Wang         2017-12-25   94  		case -EPROBE_DEFER:
3bafc09e779710a Baolin Wang         2017-12-25   95  			goto err_regmap;
3bafc09e779710a Baolin Wang         2017-12-25   96  		}
3bafc09e779710a Baolin Wang         2017-12-25   97  	}
3bafc09e779710a Baolin Wang         2017-12-25   98  
7ff7d5ffb7259f7 Andy Shevchenko     2022-05-31   99  	syscon_config.name = kasprintf(GFP_KERNEL, "%pOFn@%pa", np, &res.start);
41673c66b3d0c09 Kunwu Chan          2023-12-04  100  	if (!syscon_config.name) {
41673c66b3d0c09 Kunwu Chan          2023-12-04  101  		ret = -ENOMEM;
41673c66b3d0c09 Kunwu Chan          2023-12-04  102  		goto err_regmap;
41673c66b3d0c09 Kunwu Chan          2023-12-04  103  	}
db2fb60cd35d2d0 Damien Riegel       2015-11-30  104  	syscon_config.reg_stride = reg_io_width;
db2fb60cd35d2d0 Damien Riegel       2015-11-30  105  	syscon_config.val_bits = reg_io_width * 8;
ca668f0edfae654 Philipp Zabel       2016-01-29  106  	syscon_config.max_register = resource_size(&res) - reg_io_width;
2e63d6fa113d362 Nishanth Menon      2024-09-03  107  	if (!syscon_config.max_register)
2e63d6fa113d362 Nishanth Menon      2024-09-03  108  		syscon_config.max_register_is_0 = true;
db2fb60cd35d2d0 Damien Riegel       2015-11-30  109  
bdb0066df96e74a Pankaj Dubey        2014-09-30  110  	regmap = regmap_init_mmio(NULL, base, &syscon_config);
56a1188159cb2b8 Limeng              2021-04-07  111  	kfree(syscon_config.name);
bdb0066df96e74a Pankaj Dubey        2014-09-30  112  	if (IS_ERR(regmap)) {
bdb0066df96e74a Pankaj Dubey        2014-09-30  113  		pr_err("regmap init failed\n");
bdb0066df96e74a Pankaj Dubey        2014-09-30  114  		ret = PTR_ERR(regmap);
bdb0066df96e74a Pankaj Dubey        2014-09-30  115  		goto err_regmap;
bdb0066df96e74a Pankaj Dubey        2014-09-30  116  	}
bdb0066df96e74a Pankaj Dubey        2014-09-30  117  
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  118  	if (check_res) {
a00406b71c5f08f Fabrice Gasnier     2018-12-12  119  		clk = of_clk_get(np, 0);
a00406b71c5f08f Fabrice Gasnier     2018-12-12  120  		if (IS_ERR(clk)) {
a00406b71c5f08f Fabrice Gasnier     2018-12-12  121  			ret = PTR_ERR(clk);
a00406b71c5f08f Fabrice Gasnier     2018-12-12  122  			/* clock is optional */
a00406b71c5f08f Fabrice Gasnier     2018-12-12  123  			if (ret != -ENOENT)
a00406b71c5f08f Fabrice Gasnier     2018-12-12  124  				goto err_clk;
a00406b71c5f08f Fabrice Gasnier     2018-12-12  125  		} else {
a00406b71c5f08f Fabrice Gasnier     2018-12-12  126  			ret = regmap_mmio_attach_clk(regmap, clk);
a00406b71c5f08f Fabrice Gasnier     2018-12-12  127  			if (ret)
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  128  				goto err_attach_clk;
a00406b71c5f08f Fabrice Gasnier     2018-12-12  129  		}
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  130  
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  131  		reset = of_reset_control_get_optional_exclusive(np, NULL);
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  132  		if (IS_ERR(reset)) {
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  133  			ret = PTR_ERR(reset);
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  134  			goto err_attach_clk;
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  135  		}
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  136  
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  137  		ret = reset_control_deassert(reset);
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  138  		if (ret)
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  139  			goto err_reset;
39233b7c611248c Paul Cercueil       2019-07-24  140  	}
a00406b71c5f08f Fabrice Gasnier     2018-12-12  141  
bdb0066df96e74a Pankaj Dubey        2014-09-30  142  	syscon->regmap = regmap;
bdb0066df96e74a Pankaj Dubey        2014-09-30  143  	syscon->np = np;
bdb0066df96e74a Pankaj Dubey        2014-09-30  144  
bdb0066df96e74a Pankaj Dubey        2014-09-30  145  	list_add_tail(&syscon->list, &syscon_list);
87d687301f38072 Dong Aisheng        2012-09-05  146  
82f898f47112bc7 Krzysztof Kozlowski 2024-07-07  147  	return_ptr(syscon);
bdb0066df96e74a Pankaj Dubey        2014-09-30  148  
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  149  err_reset:
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  150  	reset_control_put(reset);
7d1e3bd94828ad9 Jeremy Kerr         2023-01-05  151  err_attach_clk:
a00406b71c5f08f Fabrice Gasnier     2018-12-12  152  	if (!IS_ERR(clk))
a00406b71c5f08f Fabrice Gasnier     2018-12-12  153  		clk_put(clk);
a00406b71c5f08f Fabrice Gasnier     2018-12-12  154  err_clk:
a00406b71c5f08f Fabrice Gasnier     2018-12-12  155  	regmap_exit(regmap);
bdb0066df96e74a Pankaj Dubey        2014-09-30  156  err_regmap:
bdb0066df96e74a Pankaj Dubey        2014-09-30 @157  	iounmap(base);
bdb0066df96e74a Pankaj Dubey        2014-09-30  158  	return ERR_PTR(ret);
87d687301f38072 Dong Aisheng        2012-09-05  159  }
87d687301f38072 Dong Aisheng        2012-09-05  160  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH v3 3/3] soc: aspeed: lpc-pcc: Add PCC controller support
Posted by Krzysztof Kozlowski 11 months ago
On 10/03/2025 12:48, Kevin Chen wrote:
> +static int aspeed_pcc_probe(struct platform_device *pdev)
> +{
> +	int rc;
> +	struct aspeed_pcc_ctrl *pcc;
> +	struct device *dev = &pdev->dev;
> +	uint32_t fifo_size = PAGE_SIZE;
> +
> +	pcc = devm_kzalloc(dev, sizeof(*pcc), GFP_KERNEL);
> +	if (!pcc)
> +		return -ENOMEM;
> +
> +	pcc->regmap = syscon_node_to_regmap(dev->parent->of_node);
> +	if (IS_ERR(pcc->regmap)) {
> +		dev_err(dev, "Couldn't get regmap\n");

return dev_err_probe() is not suitable?

> +		return -ENODEV;

Why overriding error code?

> +	}
> +
> +	rc = of_property_read_u32(dev->of_node, "pcc-ports", &pcc->port);
> +	if (rc) {
> +		dev_err(dev, "no pcc ports configured\n");
> +		return -ENODEV;

Why overriding error code?

You got this comment already at v2.

> +	}
> +
> +	rc = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
> +	if (rc) {
> +		dev_err(dev, "cannot set 64-bits DMA mask\n");
> +		return rc;
> +	}
> +
> +	pcc->dma.size = PCC_DMA_BUFSZ;
> +	pcc->dma.virt = dmam_alloc_coherent(dev,
> +					    pcc->dma.size,
> +					    &pcc->dma.addr,
> +					    GFP_KERNEL);
> +	if (!pcc->dma.virt) {
> +		dev_err(dev, "cannot allocate DMA buffer\n");
> +		return -ENOMEM;
> +	}
> +
> +	fifo_size = roundup(pcc->dma.size, PAGE_SIZE);
> +	rc = kfifo_alloc(&pcc->fifo, fifo_size, GFP_KERNEL);
> +	if (rc) {

Drop {}

> +		return -ENOMEM;
> +	}
> +

Please run scripts/checkpatch.pl and fix reported warnings. After that,
run also `scripts/checkpatch.pl --strict` and (probably) fix more
warnings. Some warnings can be ignored, especially from --strict run,
but the code here looks like it needs a fix. Feel free to get in touch
if the warning is not clear.



Best regards,
Krzysztof