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-rw-r--r--src/cpu/samsung/exynos5420/i2c.c243
1 files changed, 91 insertions, 152 deletions
diff --git a/src/cpu/samsung/exynos5420/i2c.c b/src/cpu/samsung/exynos5420/i2c.c
index 5ea1eef5de..cbe7a79c0a 100644
--- a/src/cpu/samsung/exynos5420/i2c.c
+++ b/src/cpu/samsung/exynos5420/i2c.c
@@ -46,6 +46,14 @@
#define HSI2C_TXCHON (1u << 7) /* Read/Receive */
#define HSI2C_SW_RST (1u << 31)
+/* I2C_FIFO_STAT Register bits */
+#define HSI2C_TX_FIFO_LEVEL (0x7f << 0)
+#define HSI2C_TX_FIFO_FULL (1u << 7)
+#define HSI2C_TX_FIFO_EMPTY (1u << 8)
+#define HSI2C_RX_FIFO_LEVEL (0x7f << 16)
+#define HSI2C_RX_FIFO_FULL (1u << 23)
+#define HSI2C_RX_FIFO_EMPTY (1u << 24)
+
/* I2C_FIFO_CTL Register bits */
#define HSI2C_RXFIFO_EN (1u << 0)
#define HSI2C_TXFIFO_EN (1u << 1)
@@ -77,11 +85,11 @@
/* I2C_TRANS_STATUS register bits */
#define HSI2C_MASTER_BUSY (1u << 17)
#define HSI2C_SLAVE_BUSY (1u << 16)
+#define HSI2C_TIMEOUT_AUTO (1u << 4)
#define HSI2C_NO_DEV (1u << 3)
#define HSI2C_NO_DEV_ACK (1u << 2)
#define HSI2C_TRANS_ABORT (1u << 1)
#define HSI2C_TRANS_DONE (1u << 0)
-#define HSI2C_TIMEOUT_AUTO (0u << 0)
#define HSI2C_SLV_ADDR_MAS(x) ((x & 0x3ff) << 10)
@@ -205,48 +213,11 @@ static int WaitForXfer(struct s3c24x0_i2c *i2c)
return I2C_NOK_TOUT;
}
-static int hsi2c_wait_for_irq(struct exynos5_hsi2c *i2c)
-{
- struct mono_time current, end;
- int ret = I2C_NOK_TOUT;
-
- timer_monotonic_get(&current);
- end = current;
- mono_time_add_usecs(&end, HSI2C_TIMEOUT * 1000 * 10);
-
- while (mono_time_before(&current, &end)) {
- udelay(20);
- if (read32(&i2c->usi_int_stat) &
- (HSI2C_INT_I2C_EN | HSI2C_INT_TX_ALMOSTEMPTY_EN)) {
- ret = I2C_OK;
- break;
- }
- /* wait for a while and retry */
- timer_monotonic_get(&current);
- }
-
- if (ret == I2C_NOK_TOUT)
- printk(BIOS_ERR, "%s timed out\n", __func__);
- return ret;
-}
-
-static int hsi2c_isack(struct exynos5_hsi2c *i2c)
-{
- return read32(&i2c->usi_trans_status) &
- (HSI2C_NO_DEV | HSI2C_NO_DEV_ACK);
-}
-
static void ReadWriteByte(struct s3c24x0_i2c *i2c)
{
writel(read32(&i2c->iiccon) & ~I2CCON_IRPND, &i2c->iiccon);
}
-static void hsi2c_clear_irqpd(struct exynos5_hsi2c *i2c)
-{
- u32 stat = read32(&i2c->usi_int_stat);
- write32(stat, &i2c->usi_int_stat);
-}
-
static void i2c_ch_init(struct s3c24x0_i2c_bus *bus, int speed, int slaveadd)
{
unsigned long freq, pres = 16, div;
@@ -346,6 +317,12 @@ static void hsi2c_ch_init(struct s3c24x0_i2c_bus *i2c_bus)
write32(i2c_timing_s2, &hsregs->usi_timing_fs2);
write32(i2c_timing_s3, &hsregs->usi_timing_fs3);
write32(i2c_timing_sla, &hsregs->usi_timing_sla);
+
+ /* Enable TXFIFO and RXFIFO */
+ write32(HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN, &hsregs->usi_fifo_ctl);
+
+ /* i2c_conf configure */
+ write32(readl(&hsregs->usi_conf) | HSI2C_AUTO_MODE, &hsregs->usi_conf);
}
/* SW reset for the high speed bus */
@@ -386,34 +363,61 @@ void i2c_init(unsigned bus_num, int speed, int slaveadd)
}
/*
- * Send a STOP event and wait for it to have completed
- *
- * @param mode If it is a master transmitter or receiver
- * @return I2C_OK if the line became idle before timeout I2C_NOK_TOUT otherwise
+ * Check whether the transfer is complete.
+ */
+static int hsi2c_check_transfer(struct exynos5_hsi2c *i2c)
+{
+ uint32_t status = read32(&i2c->usi_trans_status);
+ if (status & HSI2C_TRANS_ABORT)
+ printk(BIOS_ERR, "%s: Transaction aborted.\n", __func__);
+ if (status & HSI2C_NO_DEV_ACK)
+ printk(BIOS_ERR, "%s: No ack from device.\n", __func__);
+ if (status & HSI2C_NO_DEV)
+ printk(BIOS_ERR, "%s: No response from device.\n", __func__);
+ if (status & HSI2C_TIMEOUT_AUTO)
+ printk(BIOS_ERR, "%s: Transaction time out.\n", __func__);
+ return !!(status & HSI2C_MASTER_BUSY);
+}
+
+/*
+ * Wait for the transfer to finish.
*/
-static int hsi2c_send_stop(struct exynos5_hsi2c *i2c, int result)
+static int hsi2c_wait_for_transfer(struct exynos5_hsi2c *i2c)
{
- int ret = I2C_NOK_TOUT;
struct mono_time current, end;
timer_monotonic_get(&current);
end = current;
mono_time_add_usecs(&end, HSI2C_TIMEOUT * 1000);
while (mono_time_before(&current, &end)) {
- if (!(read32(&i2c->usi_trans_status) & HSI2C_MASTER_BUSY)) {
- ret = I2C_OK;
- break;
- }
+ if (!hsi2c_check_transfer(i2c))
+ return 0;
udelay(5);
timer_monotonic_get(&current);
}
- if (ret)
- printk(BIOS_ERR, "%s timed out\n", __func__);
- /* Setting the STOP event to fire */
- write32(HSI2C_FUNC_MODE_I2C, &i2c->usi_ctl);
- write32(0x0, &i2c->usi_int_en);
+ return 1;
+}
+
+static int hsi2c_senddata(struct exynos5_hsi2c *i2c, uint8_t *data, int len)
+{
+ while (hsi2c_check_transfer(i2c) && len) {
+ if (!(read32(&i2c->usi_fifo_stat) & HSI2C_TX_FIFO_FULL)) {
+ write32(*data++, &i2c->usi_txdata);
+ len--;
+ }
+ }
+ return len ? -1 : 0;
+}
- return (result == I2C_OK) ? ret : result;
+static int hsi2c_recvdata(struct exynos5_hsi2c *i2c, uint8_t *data, int len)
+{
+ while (hsi2c_check_transfer(i2c) && len) {
+ if (!(read32(&i2c->usi_fifo_stat) & HSI2C_RX_FIFO_EMPTY)) {
+ *data++ = read32(&i2c->usi_rxdata);
+ len--;
+ }
+ }
+ return len ? -1 : 0;
}
static int hsi2c_write(struct exynos5_hsi2c *i2c,
@@ -423,83 +427,33 @@ static int hsi2c_write(struct exynos5_hsi2c *i2c,
unsigned char data[],
unsigned short len)
{
- int i = 0, result = I2C_OK;
- u32 i2c_auto_conf;
- u32 stat;
- struct mono_time current, end;
-
- /* Check I2C bus idle */
- i = HSI2C_TIMEOUT * 20;
- timer_monotonic_get(&current);
- end = current;
- mono_time_add_usecs(&end, HSI2C_TIMEOUT * 1000 * 20);
- while (mono_time_before(&current, &end)) {
- if (!(read32(&i2c->usi_trans_status) & HSI2C_MASTER_BUSY))
- break;
- udelay(50);
- timer_monotonic_get(&current);
- }
+ uint32_t i2c_auto_conf;
- stat = read32(&i2c->usi_trans_status);
-
- if (stat & HSI2C_MASTER_BUSY) {
- printk(BIOS_ERR, "%s: bus busy, timing out\n", __func__);
- return I2C_NOK_TOUT;
- }
- /* Disable TXFIFO and RXFIFO */
- write32(0, &i2c->usi_fifo_ctl);
+ if (hsi2c_wait_for_transfer(i2c))
+ return -1;
/* chip address */
write32(HSI2C_SLV_ADDR_MAS(chip), &i2c->i2c_addr);
- /* Enable interrupts */
- write32((HSI2C_INT_I2C_EN | HSI2C_INT_TX_ALMOSTEMPTY_EN),
- &i2c->usi_int_en);
-
/* usi_ctl enable i2c func, master write configure */
write32((HSI2C_TXCHON | HSI2C_FUNC_MODE_I2C | HSI2C_MASTER),
&i2c->usi_ctl);
- /* i2c_conf configure */
- write32(readl(&i2c->usi_conf) | HSI2C_AUTO_MODE, &i2c->usi_conf);
-
/* auto_conf for write length and stop configure */
i2c_auto_conf = ((len + alen) | HSI2C_STOP_AFTER_TRANS);
i2c_auto_conf &= ~HSI2C_READ_WRITE;
- write32(i2c_auto_conf, &i2c->usi_auto_conf);
-
/* Master run, start xfer */
- write32(read32(&i2c->usi_auto_conf) | HSI2C_MASTER_RUN,
- &i2c->usi_auto_conf);
-
- result = hsi2c_wait_for_irq(i2c);
- if ((result == I2C_OK) && hsi2c_isack(i2c)) {
- printk(BIOS_ERR, "%s: NAK from device %04x\n", __func__,
- HSI2C_SLV_ADDR_MAS(chip));
- result = I2C_NACK;
- goto out;
- }
+ i2c_auto_conf |= HSI2C_MASTER_RUN;
+ write32(i2c_auto_conf, &i2c->usi_auto_conf);
- for (i = 0; i < alen && (result == I2C_OK); i++) {
- write32(addr[i], &i2c->usi_txdata);
- result = hsi2c_wait_for_irq(i2c);
- hsi2c_clear_irqpd(i2c);
- if (result)
- printk(BIOS_ERR, "%s: timeout on sending address\n",
- __func__);
+ if (hsi2c_senddata(i2c, addr, alen) ||
+ hsi2c_senddata(i2c, data, len) ||
+ hsi2c_wait_for_transfer(i2c)) {
+ return -1;
}
- for (i = 0; i < len && (result == I2C_OK); i++) {
- write32(data[i], &i2c->usi_txdata);
- result = hsi2c_wait_for_irq(i2c);
- hsi2c_clear_irqpd(i2c);
- if (result)
- printk(BIOS_ERR, "%s: timeout on sending data\n",
- __func__);
- }
-out:
- hsi2c_clear_irqpd(i2c);
- return hsi2c_send_stop(i2c, result);
+ write32(HSI2C_FUNC_MODE_I2C, &i2c->usi_ctl);
+ return 0;
}
static int hsi2c_read(struct exynos5_hsi2c *i2c,
@@ -510,60 +464,45 @@ static int hsi2c_read(struct exynos5_hsi2c *i2c,
unsigned short len,
int check)
{
- int i, result;
- u32 i2c_auto_conf;
-
- if (!check) {
- result = hsi2c_write(i2c, chip, addr, alen, data, 0);
- if (result != I2C_OK) {
- printk(BIOS_ERR, "write failed Result: %d\n", result);
- return result;
- }
- }
+ uint32_t i2c_auto_conf;
/* start read */
- /* Disable TXFIFO and RXFIFO */
- write32(0, &i2c->usi_fifo_ctl);
+ if (hsi2c_wait_for_transfer(i2c))
+ return -1;
/* chip address */
write32(HSI2C_SLV_ADDR_MAS(chip), &i2c->i2c_addr);
- /* Enable interrupts */
- write32(HSI2C_INT_I2C_EN, &i2c->usi_int_en);
+ /* usi_ctl enable i2c func, master write configure */
+ write32((HSI2C_TXCHON | HSI2C_FUNC_MODE_I2C | HSI2C_MASTER),
+ &i2c->usi_ctl);
- /* i2c_conf configure */
- write32(read32(&i2c->usi_conf) | HSI2C_AUTO_MODE, &i2c->usi_conf);
+ /* auto_conf */
+ write32(alen | HSI2C_MASTER_RUN | HSI2C_STOP_AFTER_TRANS,
+ &i2c->usi_auto_conf);
- /* auto_conf, length and stop configure */
- i2c_auto_conf = (len | HSI2C_STOP_AFTER_TRANS | HSI2C_READ_WRITE);
- write32(i2c_auto_conf, &i2c->usi_auto_conf);
+ if (hsi2c_senddata(i2c, addr, alen) ||
+ hsi2c_wait_for_transfer(i2c)) {
+ return -1;
+ }
/* usi_ctl enable i2c func, master WRITE configure */
write32((HSI2C_RXCHON | HSI2C_FUNC_MODE_I2C | HSI2C_MASTER),
&i2c->usi_ctl);
+ /* auto_conf, length and stop configure */
+ i2c_auto_conf = (len | HSI2C_STOP_AFTER_TRANS | HSI2C_READ_WRITE);
+ i2c_auto_conf |= HSI2C_MASTER_RUN;
/* Master run, start xfer */
- write32(readl(&i2c->usi_auto_conf) | HSI2C_MASTER_RUN,
- &i2c->usi_auto_conf);
+ write32(i2c_auto_conf, &i2c->usi_auto_conf);
- result = hsi2c_wait_for_irq(i2c);
- if ((result == I2C_OK) && hsi2c_isack(i2c)) {
- result = I2C_NACK;
- goto out;
+ if (hsi2c_recvdata(i2c, data, len) ||
+ hsi2c_wait_for_transfer(i2c)) {
+ return -1;
}
- for (i = 0; i < len && (result == I2C_OK); i++) {
- result = hsi2c_wait_for_irq(i2c);
- data[i] = read32(&i2c->usi_rxdata);
- udelay(100);
- }
- /*for(i = 0; i < len; i++)
- printk(BIOS_SPEW, " %02x", data[i]);
- printk(BIOS_SPEW, "\n");*/
-out:
- /* Stop and quit */
- hsi2c_clear_irqpd(i2c);
- return hsi2c_send_stop(i2c, result);
+ write32(HSI2C_FUNC_MODE_I2C, &i2c->usi_ctl);
+ return 0;
}
/*
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-23 05:24:22 +0000