qcom平台LK 阶段配置IIC

版本号：V 1.0

作者：Leo

struct qup_i2c_dev *qup_blsp_i2c_init(uint8_t blsp_id, uint8_t qup_id,uint32_t clk_freq, uint32_t src_clk_freq)
{struct qup_i2c_dev *dev;if (dev_addr != NULL) {return dev_addr;}dev = malloc(sizeof(struct qup_i2c_dev));if (!dev) {return NULL;}dev = memset(dev, 0, sizeof(struct qup_i2c_dev));/* Platform uses BLSP */dev->qup_irq = BLSP_QUP_IRQ(blsp_id, qup_id);dev->qup_base = BLSP_QUP_BASE(blsp_id, qup_id);/* This must be done for qup_i2c_interrupt to work. */dev_addr = dev;/* Initialize the GPIO for BLSP i2c */gpio_config_blsp_i2c(blsp_id, qup_id);clock_config_blsp_i2c(blsp_id, qup_id);qup_i2c_sec_init(dev, clk_freq, src_clk_freq);return dev;
}

从以上流程看，有5个需要关注的地方

1. dev->qup_irq = BLSP_QUP_IRQ(blsp_id, qup_id);
2. dev->qup_base = BLSP_QUP_BASE(blsp_id, qup_id);
3. gpio_config_blsp_i2c(blsp_id, qup_id);
4. clock_config_blsp_i2c(blsp_id, qup_id);
5. qup_i2c_sec_init(dev, clk_freq, src_clk_freq);  // 略过，I2C的初始化过程

一个一个分析：

2.1 qup irq 中断号赋值

dev->qup_irq = BLSP_QUP_IRQ(blsp_id, qup_id);

中断号，使用 BLSP_QUP_IRQ 这个宏来赋值，那么找到它的定义：

bootable\bootloader\lk\platform\msm8909\include\platform\irqs.h#define GIC_SPI_START                          32#define BLSP_QUP_IRQ(blsp_id, qup_id)          (GIC_SPI_START + 95 + qup_id)

从章节1的qup 信息可知，qup6的中断号为100，那么传参qup_id 为5，中断号为

GIC_SPI_START + 95 + 5， GIC_SPI_START 是一个偏移量，不用管它。

这里大概可以推测，qup_id 应该传参为5。

2.2 qup base addr 赋值

dev->qup_base = BLSP_QUP_BASE(blsp_id, qup_id);

qup 基地址的赋值，使用 BLSP_QUP_BASE来赋值，找到它的定义

bootable\bootloader\lk\platform\msm8909\include\platform\iomap.h#define PERIPH_SS_BASE              0x07800000bootable\bootloader\lk\platform\msm8909\include\platform\iomap.h#define BLSP_QUP_BASE(blsp_id, qup_id) (PERIPH_SS_BASE + 0xB5000 + 0x1000 * qup_id)

从章节1的qup信息图得知，qup6的 base addr 为78ba000，那么这里qup_id 传参应该为5

即：0x70800000 + 0x0B5000 + 0x1000 * 5 = 0x78bA000

到此为止，从qup irq的信息和qup base addr的信息确认，那么I2C-6(gpio10、gpio11)对应的qup 传参应该是 QUP_ID_5。

2.3 blsp6 gpio 初始化

/* Initialize the GPIO for BLSP i2c */gpio_config_blsp_i2c(blsp_id, qup_id);

看gpio_config_blsp_i2c函数定义.

void gpio_config_blsp_i2c(uint8_t blsp_id, uint8_t qup_id)
{
#if DSI2DPI_TC358762uint32_t hw_id = board_hardware_id();uint32_t hw_subtype = board_hardware_subtype();
#endifif(blsp_id == BLSP_ID_1) {switch (qup_id) {case QUP_ID_1:/* configure I2C SDA gpio */gpio_tlmm_config(6, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(7, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);break;case QUP_ID_2:/* configure I2C SDA gpio */gpio_tlmm_config(111, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(112, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);break;case QUP_ID_3:/* configure I2C SDA gpio */gpio_tlmm_config(29, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(30, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);break;case QUP_ID_4:
#if DSI2DPI_TC358762if ((HW_PLATFORM_SUBTYPE_LR3001 == hw_subtype)&& (HW_PLATFORM_MTP == hw_id)) {/* configure I2C SDA gpio */gpio_tlmm_config(18, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_2MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(19, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_2MA, GPIO_DISABLE);} else {
#endif/* configure I2C SDA gpio */gpio_tlmm_config(14, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(15, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);
#if DSI2DPI_TC358762}
#endifbreak;case QUP_ID_5:/* configure I2C SDA gpio */gpio_tlmm_config(18, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(19, 3, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);
/* Begin: add by leo for add i2c-6(gpio_10 & gpio_11) */
#if 1/* configure I2C SDA gpio */gpio_tlmm_config(10, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(11, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);dprintf(CRITICAL, "leo i2c-%d (gpio10 & gpio11)\n", qup_id + 1);
#endif
/* End: add by leo for add i2c-6(gpio_10 & gpio_11) */break;default:dprintf(CRITICAL, "Incorrect QUP id %d\n",qup_id);ASSERT(0);};} else {dprintf(CRITICAL, "Incorrect BLSP id %d\n",blsp_id);ASSERT(0);}
}

从以上调用流程可以看出，整个流程就是根据BLSP_ID 和QUP_ID 去初始化不同的gpio。

所以在这里，需要判断在 case QUP_ID_5 中是否已经包含我们需要的gpio管脚(gpio10、gpio11)的初配置。

代码修改：

/* Begin: add by leo for add i2c-6(gpio_10 & gpio_11) */
#if 1/* configure I2C SDA gpio */gpio_tlmm_config(10, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(11, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);dprintf(CRITICAL, "leo i2c-%d (gpio10 & gpio11)\n", qup_id + 1);
#endif
/* End: add by leo for add i2c-6(gpio_10 & gpio_11) */

显然没有，那么就需要在case QUP_ID_5：新增 gpio10、gpio11的初始化。

注意这里：这里配置为功能2，是复用为i2c功能

依据：

80-np408-2x_c_msm8909_msm8209_msm8208_hardware_register_description_document_for_oems.pdf

page-2624 介绍：

配置为功能 2 是 IIC功能。

2.4 blsp6 时钟源的配置

clock_config_blsp_i2c(blsp_id, qup_id);

看函数定义：

void clock_config_blsp_i2c(uint8_t blsp_id, uint8_t qup_id)
{uint8_t ret = 0;char clk_name[64];struct clk *qup_clk;qup_id = qup_id + 1;if((blsp_id != BLSP_ID_1)) {dprintf(CRITICAL, "Incorrect BLSP-%d configuration\n", blsp_id);ASSERT(0);}snprintf(clk_name, sizeof(clk_name), "blsp1_qup%u_ahb_iface_clk", qup_id);dprintf(CRITICAL, "leo i2c-%d clk_name=%s \n", qup_id, clk_name);ret = clk_get_set_enable(clk_name, 0 , 1);if (ret) {dprintf(CRITICAL, "Failed to enable %s clock\n", clk_name);return;}snprintf(clk_name, sizeof(clk_name), "gcc_blsp1_qup%u_i2c_apps_clk", qup_id);dprintf(CRITICAL, "leo i2c-%d clk_name=%s \n", qup_id, clk_name);qup_clk = clk_get(clk_name);if (!qup_clk) {dprintf(CRITICAL, "Failed to get %s\n", clk_name);return;}ret = clk_enable(qup_clk);if (ret) {dprintf(CRITICAL, "Failed to enable %s\n", clk_name);return;}
}

首先，qup_id = qup_id + 1; 这里，对qup进行了自加1，那么下面对应的时钟源参数就变成了blsp6。

且能看出，需要的是 blsp1_qup6_ahb_iface_clk 和 gcc_blsp1_qup6_i2c_apps_clk，这两个时钟源。

 snprintf(clk_name, sizeof(clk_name), "blsp1_qup%u_ahb_iface_clk", qup_id);dprintf(CRITICAL, "leo i2c-%d clk_name=%s \n", qup_id, clk_name);ret = clk_get_set_enable(clk_name, 0 , 1);if (ret) {dprintf(CRITICAL, "Failed to enable %s clock\n", clk_name);return;}snprintf(clk_name, sizeof(clk_name), "gcc_blsp1_qup%u_i2c_apps_clk", qup_id);dprintf(CRITICAL, "leo i2c-%d clk_name=%s \n", qup_id, clk_name);qup_clk = clk_get(clk_name);

可以看clk_get_set_enable 和 clk_get 的定义

clk_get_set_enable：

bootable\bootloader\lk\platform\msm_shared\clock.c

函数定义略

clk_get：

bootable\bootloader\lk\platform\msm_shared\clock.c

struct clk *clk_get (const char * cid)
{unsigned i;struct clk_lookup *cl= msm_clk_list.clist;unsigned num = msm_clk_list.num;if(!cl || !num){dprintf (CRITICAL, "Alert!! clock list not defined!\n");return NULL;}for(i=0; i < num; i++, cl++){if(!strcmp(cl->con_id, cid)){return cl->clk;}}dprintf(CRITICAL, "Alert!! Requested clock \"%s\" is not supported!\n", cid);return NULL;
}

分析：都是从 bootable\bootloader\lk\platform\msm_shared\clock.c 中的static struct clk_list msm_clk_list; 全局clk list 中获取的信息。

找到在哪初始化的：

路径：
bootable\bootloader\lk\platform\msm_shared\clock.cvoid clk_init(struct clk_lookup *clist, unsigned num)
{if(clist && num){msm_clk_list.clist = (struct clk_lookup *)clist;msm_clk_list.num = num;}
}

找到在哪调用的：

路径：bootable\bootloader\lk\platform\msm8909\msm8909-clock.cvoid platform_clock_init(void)
{clk_init(msm_clocks_msm8909, ARRAY_SIZE(msm_clocks_msm8909));
}

其中msm_clocks_msm8909 这个clk 结构体数组，就是我们要修改的目标。

此处需对应 clock_config_blsp_i2c 函数中的分析。

最终我们需要的有三个时钟源配置，根据实际代码去修改。

bootable\bootloader\lk\platform\msm8909\msm8909-clock.c
msm_clocks_msm8909 数组中#elseCLK_LOOKUP("blsp1_qup6_ahb_iface_clk", gcc_blsp1_ahb_clk.c),CLK_LOOKUP("gcc_blsp1_qup6_i2c_apps_clk_src", gcc_blsp1_qup6_i2c_apps_clk_src.c),CLK_LOOKUP("gcc_blsp1_qup6_i2c_apps_clk", gcc_blsp1_qup6_i2c_apps_clk.c),
#endif

4. 总结

那么总结下，所有的配置修改。

1. 调用I2C 初始化函数

struct qup_i2c_dev *
qup_blsp_i2c_init(uint8_t blsp_id, uint8_t qup_id, uint32_t clk_freq, uint32_t src_clk_freq)

2. 检查gpio配置

查看I2C对应的gpio配置是否包含，否则去添加

/* Begin: add by leo for add i2c-6(gpio_10 & gpio_11) */
#if 1/* configure I2C SDA gpio */gpio_tlmm_config(10, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);/* configure I2C SCL gpio */gpio_tlmm_config(11, 2, GPIO_OUTPUT, GPIO_NO_PULL,GPIO_8MA, GPIO_DISABLE);dprintf(CRITICAL, "leo i2c-%d (gpio10 & gpio11)\n", qup_id + 1);
#endif
/* End: add by leo for add i2c-6(gpio_10 & gpio_11) */

3. 检查I2C src clk 配置，没有则添加

bootable\bootloader\lk\platform\msm8909\msm8909-clock.c
msm_clocks_msm8909 数组中#elseCLK_LOOKUP("blsp1_qup6_ahb_iface_clk", gcc_blsp1_ahb_clk.c),CLK_LOOKUP("gcc_blsp1_qup6_i2c_apps_clk_src", gcc_blsp1_qup6_i2c_apps_clk_src.c),CLK_LOOKUP("gcc_blsp1_qup6_i2c_apps_clk", gcc_blsp1_qup6_i2c_apps_clk.c),
#endif

4. I2C 读函数demo。 (寄存器地址和数据都以8bit为例)

static uint8_t adv7533_i2c_read(uint8_t slave_addr, uint8_t reg)
{int ret;int err_return = -1;uint8_t value;dprintf(SPEW, "%s: Leo enter \n", __func__);uint8_t tx_data[] = {reg & 0xff,};uint8_t rx_data[1];struct i2c_msg msgs[] = {{.addr = slave_addr,.flags = I2C_M_WR,.buf = tx_data,.len = ADV_ARRAY_SIZE(tx_data),},{.addr = slave_addr,.flags = I2C_M_RD,.buf = rx_data,.len = ADV_ARRAY_SIZE(rx_data),}};ret = qup_i2c_xfer(i2c6_dev, msgs, ADV_ARRAY_SIZE(msgs));if (ret < 0) {dprintf(CRITICAL, "%s: reg 0x%04x error %d\n", __func__, reg, ret);return ret;}if (ret < ADV_ARRAY_SIZE(msgs)) {dprintf(CRITICAL, "%s: reg 0x%04x msgs %d\n", __func__, reg, ret);return err_return;}value = rx_data[0];dprintf(CRITICAL, "%s: reg 0x%x 0x%x\n", __func__, reg, value);return value;
}

5. I2C 写函数 demo

static int adv7533_i2c_write(uint8_t slave_addr, uint8_t reg, uint8_t value)
{int ret = 0;uint8_t tx_data[2] = {reg, value};/* Send commands via I2C */struct i2c_msg msgs[1] = {{.addr = slave_addr,.flags = I2C_M_WR, // 0.len = 2,.buf = tx_data,},};ret = qup_i2c_xfer(i2c6_dev, msgs, 1);if (ret < 0) {dprintf(CRITICAL, "%s failed ret=%d\n", __func__, ret);return ret;}mdelay(2);return 0;
}