uboot - pinctrl - FPGA回片前测试阶段 - 设置GPIO引脚复用失败

这篇具有很好参考价值的文章主要介绍了uboot - pinctrl - FPGA回片前测试阶段 - 设置GPIO引脚复用失败。希望对大家有所帮助。如果存在错误或未考虑完全的地方,请大家不吝赐教,您也可以点击"举报违法"按钮提交疑问。

问题描述

pinctrl设置引脚复用失败,没有调用到controller中的set_groups_function函数。

问题定位

  1. pinctrl如何注册dm节点
  2. 如何进行设备树中各个设备节点下的复用配置
  3. 为什么没调用到控制器实现的set_groups_function函数
&gpio0 {
	status = "okay";
    pinctrl-names = "default";
    pinctrl-0 = <&gpioa15_pinctrl>;
};

&pinctrl {
    gpioa15 {
        gpioa15_pinctrl: gpioa15_grp {
            ts,pins = <PB7>;
            mux,val = <5>;
            function = "gpioa15";
            groups = "gpioa15_grp";
        };
    };
};

pinctrl如何注册dm节点

调用过程:

[uboot/drivers/core/device.c]
int device_probe(struct udevice *dev)
	 /* Process pinctrl for everything except the root device, and
	 * continue regardless of the result of pinctrl. Don't process pinctrl
	 * settings for pinctrl devices since the device may not yet be
	 * probed. 
	 * */
	pinctrl_select_state(dev, "default");
		pinctrl_select_state_simple(dev);
		/*
		 * Try full-implemented pinctrl first.
		 * If it fails or is not implemented, try simple one.
		 */
			if (pinctrl_select_state_full(dev, statename))
				return pinctrl_select_state_simple(dev);
	UCLASS_DRIVER(pinctrl) = {
	.id = UCLASS_PINCTRL,
	.post_bind = pinctrl_post_bind,
	.flags = DM_UC_FLAG_SEQ_ALIAS,
	.name = "pinctrl",

	ret = uclass_pre_probe_device(dev);
	ret = uclass_post_probe_device(dev);
		uc_drv->post_probe
			pinctrl_post_bind
				return pinconfig_post_bind(dev);
	pinctrl_select_state(dev, "default");
		pinctrl_select_state_full(dev, statename)
			ret = pinctrl_config_one(config);
				ops = pinctrl_get_ops(pctldev);
				/* this ops was set by controller */
				return ops->set_state(pctldev, config);
	
};

上面的调用过程是通过加log找出来的,log如下:

__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
initr_nand bypass                                                                                                                   
MMC:   __file:drivers/core/device.c __func:device_probe __line:431                                                                  
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
dev 0x00000000bf741ec0, size 0xa0, name mmc@f0512000, ofnode 10c4, mmc@f0512000                                                     
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
dev 0x00000000bf742260, size 0xa0, name mmc@f0513000, ofnode 1158, mmc@f0513000                                                     
__file:drivers/core/device.c __func:device_probe __line:431        

看着就是在pinctrl_select_state_full 函数里出了问题:
每次进入pinctrl_select_state_full 函数只能打印到68行,下面的打印出不来,没有调到pinctrl_config_one,所以设备树里注册的gpioa15_pinctrl没有被配置。

/**
 * pinctrl_select_state_full() - full implementation of pinctrl_select_state
 *
 * @dev: peripheral device
 * @statename: state name, like "default"
 * @return: 0 on success, or negative error code on failure
 */
static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
{
	char propname[32]; /* long enough */
	const fdt32_t *list;
	uint32_t phandle;
	struct udevice *config;
	int state, size, i, ret;

printf("__file:%s __func:%s __line:%d\n", __FILE__, __func__, __LINE__);
	state = dev_read_stringlist_search(dev, "pinctrl-names", statename);
	if (state < 0) {
		char *end;
		/*
		 * If statename is not found in "pinctrl-names",
		 * assume statename is just the integer state ID.
		 */
		state = simple_strtoul(statename, &end, 10);
		if (*end)
			return -EINVAL;
	}
printf("__file:%s __func:%s __line:%d\n", __FILE__, __func__, __LINE__);
	snprintf(propname, sizeof(propname), "pinctrl-%d", state);
	list = dev_read_prop(dev, propname, &size);
	if (!list)
		return -EINVAL;

	size /= sizeof(*list);
    printf("__file:%s __func:%s __line:%d size:%d\n", __FILE__, __func__, __LINE__, size);
	for (i = 0; i < size; i++) {
		phandle = fdt32_to_cpu(*list++);
		ret = uclass_get_device_by_phandle_id(UCLASS_PINCONFIG, phandle,
						      &config);
		if (ret) {
			dev_warn(dev, "%s: uclass_get_device_by_phandle_id: err=%d\n",
				__func__, ret);
			continue;
		}
printf("__file:%s __func:%s __line:%d\n", __FILE__, __func__, __LINE__);
		ret = pinctrl_config_one(config);
		if (ret) {
			dev_warn(dev, "%s: pinctrl_config_one: err=%d\n",
				__func__, ret);
			continue;
		}
	}

	return 0;
}

初步怀疑是69行这里state = dev_read_stringlist_search(dev, "pinctrl-names", statename); 返回的state是个非法值。打印出来看看:
果然都是非法值,-61!!!

pinctrl_probe                                                                                                                       
reg_base:f0389000                                                                                                                   
npins  : 78                                                                                                                         
nfuncs : 1                                                                                                                          
ngroups: 1                                                                                                                          
                                                                                                                                    
func:gpioa15, ngroups = 1                                                                                                           
grp_index = 0                                                                                                                       
group[0] name gpioa15_grp                                                                                                           
mux_val: 0x5                                                                                                                        
npins: 1                                                                                                                            
15                                                                                                                                  
ts_pinctrl_parse_dt done                                                                                                            
ts pinctrl initialized                                                                                                              
__file:drivers/core/device.c __func:device_probe __line:523                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70  state:-61                                       
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70  state:-61                                       
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
initr_nand bypass                                                                                                                   
MMC:   __file:drivers/core/device.c __func:device_probe __line:431                                                                  
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70  state:-61                                       
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
dev 0x00000000bf741ec0, size 0xa0, name mmc@f0512000, ofnode 10c4, mmc@f0512000                                                     
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:68                                                  
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70  state:-61                                       
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                          

uboot的异常宏号码列表
uboot/include/linux/errno.h

#define	EBFONT		59	/* Bad font file format */
#define	ENOSTR		60	/* Device not a stream */
#define	ENODATA		61	/* No data available */

dev_read_stringlist_search的定义:

static inline int dev_read_stringlist_search(const struct udevice *dev,
					     const char *propname,
					     const char *string)
{
	return ofnode_stringlist_search(dev_ofnode(dev), propname, string);
}

int ofnode_stringlist_search(ofnode node, const char *property,
			     const char *string)
{
	if (ofnode_is_np(node)) {
	//maybe bug here?
		return of_property_match_string(ofnode_to_np(node),
						property, string);
	} else {
		int ret;

		ret = fdt_stringlist_search(gd->fdt_blob,
					    ofnode_to_offset(node), property,
					    string);
		if (ret == -FDT_ERR_NOTFOUND)
			//maybe bug here?
			return -ENODATA;
		else if (ret < 0)
			return -EINVAL;

		return ret;
	}
}

上面注释中有两个位置可能返回了ENODATA,此处已经开始怀疑是不是设备树描述地有问题了。回头看了一下dts中,pinctrl-names属性是存在的。。。
但是dts虽然有,编译出dtb到后不一定还是存在的,这里通过请教前辈,有哪些fdt的调试手段,前辈推荐了fdt命令,在uboot中可以用于显示设备树信息:
如何使用:

  1. 通过printenv,找到fdtcontroladdr属性的值,此为fdt所在地址
  2. 运行fdt fdtcontroladdr
  3. 运行fdt list
    找到gpio和pinctrl节点所在:
    uboot - pinctrl - FPGA回片前测试阶段 - 设置GPIO引脚复用失败,fpga开发
    可以看到gpio及其pinctrl配置,实际已经配置进去了。
    从这里开始,我就觉得不对劲了,只能开始请神了,所以我找了原先的pinctrl mantainer。原先的mantainer说:
    uboot中GPIO节点的pinctrl配置,是必须在gpio命令运行完毕之后,才会进行pinctrl的配置的!

恍然大悟,之前没有注意过这个特性,我运行了gpio set 15 1后:

=> gpio set 15 1                                                                                                                    
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
dev->name:gpio@f0390000                                                                                                             
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70                                                  
fdt_stringlist_search len:8                                                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:72  state:0 name:default                            
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:83                                                  
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:90 size:1                                           
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
dev->name:gpioa15                                                                                                                   
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70                                                  
const fdt_stringlist_search == FDT_ERR_NOTFOUND                                                                                     
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:72  state:-61 name:default                          
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
dev->name:gpioa15_grp                                                                                                               
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70                                                  
const fdt_stringlist_search == FDT_ERR_NOTFOUND                                                                                     
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:72  state:-61 name:default                          
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:100                                                 
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:32                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:34                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:36                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:38                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:44                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:36                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:38                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:44                                                         
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_config_one __line:50                                                         
__func:pinctrl_generic_set_state line:340                                                                                           
__func:pinctrl_generic_set_state_subnode line:301                                                                                   
>>>get group[0] gpioa15_grp                                                                                                         
__func:pinctrl_generic_set_state_subnode line:326                                                                                   
__func:pinctrl_generic_set_state_one line:250                                                                                       
__func:pinctrl_generic_set_state_one line:261                                                                                       
__func:pinmux_enable_setting line:119                                                                                               
set_mux, function:0, group:0                                                                                                        
group name:gpioa15_grp, func name:gpioa15 mux_val:5                                                                                 
pin15, wr 0x00000000f038912c, val 0x50000000                                                                                        
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
failed to get gpio clock                                                                                                            
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:460                                                                         
__file:drivers/core/device.c __func:device_probe __line:476                                                                         
__file:drivers/core/device.c __func:device_probe __line:479                                                                         
dev->name:pa                                                                                                                        
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:70                                                  
const fdt_stringlist_search == FDT_ERR_NOTFOUND                                                                                     
__file:drivers/pinctrl/pinctrl-uclass.c __func:pinctrl_select_state_full __line:72  state:-61 name:default                          
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:482                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
gpio: pin 15 (gpio 15) value is 1                                                                                                   
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431                                                                         
__file:drivers/core/device.c __func:device_probe __line:431  

可以看到name:default已经找到了,再使用devmem查看pinctrl对应的B组寄存器值:

=> md 0xf038912c                                                                                                                    
f038912c: 50000000 00000000 00000000 00000000    ...P............                                                                   
f038913c: 00000000 00000000 00000000 00000000    ................                                                                   
f038914c: 00000000 00000000 00000000 00000000    ................                                                                   
f038915c: 00000000 00000000 00000000 00000000    ................                                                                   
f038916c: 00000000 00000000 00000000 00000000    ................                                                                   
f038917c: 00000000 00000000 00000000 00000000    ................                                                                   
f038918c: 00000000 00000000 00000000 00000000    ................                                                                   
f038919c: 00000000 00000000 00000000 00000000    ................                                                                   
f03891ac: 00000000 00000000 00000000 00000000    ................                                                                   
f03891bc: 00000000 00000000 00000000 00000000    ................                                                                   
f03891cc: 00000000 00000000 00000000 00000000    ................                                                                   
f03891dc: 00000000 00000000 00000000 00000000    ................                                                                   
f03891ec: 00000000 00000000 00000000 00000000    ................                                                                   
f03891fc: 00000000 000000ff 00000000 00000000    ................                                                                   
f038920c: 00000000 000000ff 00000000 00000000    ................                                                                   
f038921c: 00000000 00000000 00000000 00000000    ................                                                                   
=>   

func5配置成功。

TODO:gpio中如何调用到pinctrl配置接口

推荐链接:
https://blog.csdn.net/ZHONGCAI0901/article/details/117986327文章来源地址https://www.toymoban.com/news/detail-843475.html

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