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USART: Main implemented.

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This commit is contained in:
NIIBE Yutaka
2017-12-15 13:51:55 +09:00
parent b4b9aace03
commit 7b1c442d88
1 changed files with 188 additions and 13 deletions
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201
contrib/usart-stm32.c
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@@ -46,17 +46,18 @@ struct USART {
static struct USART *const USART2 = (struct SYSCFG *)USART2_BASE;
static struct USART *const USART3 = (struct SYSCFG *)USART3_BASE;
#define USART_SR_CTS 0x0200
#define USART_SR_LBD 0x0100
#define USART_SR_TXE 0x0080
#define USART_SR_TC 0x0040
#define USART_SR_RXNE 0x0020
#define USART_SR_IDLE 0x0010
#define USART_SR_ORE 0x0008
#define USART_SR_NE 0x0004
#define USART_SR_FE 0x0002
#define USART_SR_PE 0x0001
#define USART_SR_CTS (1 << 9)
#define USART_SR_LBD (1 << 8)
#define USART_SR_TXE (1 << 7)
#define USART_SR_TC (1 << 6)
#define USART_SR_RXNE (1 << 5)
#define USART_SR_IDLE (1 << 4)
#define USART_SR_ORE (1 << 3)
#define USART_SR_NE (1 << 2)
#define USART_SR_FE (1 << 1)
#define USART_SR_PE (1 << 0)
#define USART_CR1_TXEIE (1 << 7)
static struct USART *
@@ -87,12 +88,28 @@ static const struct brr_setting brr_table[] = {
{ B921600, ( 2 << 4)|7},
};
static void *usart_main (void *arg);
struct usart_stat {
uint32_t tx;
uint32_t rx;
uint32_t rx_break;
uint32_t err_rx_overflow; /* software side */
uint32_t err_rx_overrun; /* hardware side */
uint32_t err_rx_noise;
uint32_t err_rx_parity;
};
static struct usart_stat usart2_stat;
static struct usart_stat usart3_stat;
void
usart_init (void)
{
RCC->APB1ENR |= ((1 << 18) | (1 << 17));
RCC->APB1RSTR = ((1 << 18) | (1 << 17));
RCC->APB1RSTR = 0;
}
/*
@@ -107,7 +124,7 @@ usart_init (void)
int
usart_config (uint8_t dev_no, uint32_t config_bits)
{
struct USART *dev = get_usart_dev (dev_no);
struct USART *USARTx = get_usart_dev (dev_no);
uint8_t baud_spec = (config & 0x3f);
int i;
@@ -118,7 +135,9 @@ usart_config (uint8_t dev_no, uint32_t config_bits)
if (i >= NUM_BAUD)
return -1;
dev->BRR = brr_table[i].brr_value;
USARTx->BRR = brr_table[i].brr_value;
/* No PEIE, CTSIE, TCIE, IDLEIE, LBDIE */
return 0;
}
@@ -142,7 +161,7 @@ struct rb {
/*
* Note: size = 1024 can still work, regardless of the limit of 10-bit.
*/
static init
static void
rb_init (struct rng_rb *rb, uint32_t *p, uint16_t size)
{
rb->buf = p;
@@ -274,3 +293,159 @@ rb_write (struct rng_rb *rb, uint8_t *buf, uint16_t buflen)
}
chopstx_mutex_unlock (&rb->m);
}
static int
rb_empty_check (void *arg)
{
struct rng_rb *rb = arg;
return rb->empty != 0;
}
static void
rb_get_prepare_poll (struct rb *rb, chopstx_poll_cond_t *poll_desc)
{
poll_desc->type = CHOPSTX_POLL_COND;
poll_desc->ready = 0;
poll_desc->cond = &rb->data_available;
poll_desc->mutex = &rb->m;
poll_desc->check = rb_empty_check;
poll_desc->arg = rb;
}
#define INTR_REQ_USART2 38
#define INTR_REQ_USART3 39
static uint8_t buf_usart2_rb_a2h[256];
static uint8_t buf_usart2_rb_h2a[512];
static uint8_t buf_usart3_rb_a2h[256];
static uint8_t buf_usart3_rb_h2a[512];
static struct chx_intr usart2_intr;
static struct chx_intr usart3_intr;
static struct rng_rb usart2_rb_a2h;
static struct rng_rb usart2_rb_h2a;
static struct rng_rb usart3_rb_a2h;
static struct rng_rb usart3_rb_h2a;
static chopstx_poll_cond_t usart2_app_write_event;
static chopstx_poll_cond_t usart3_app_write_event;
static struct chx_poll_head * usart_poll[4];
static int usart2_tx_ready;
static int usart3_tx_ready;
static int
handle_intr (struct USART *USARTx, struct rng_rb rb2a, struct usart_stat *stat)
{
int tx_ready = 0;
uint32_t r = USARTx->SR;
if ((r & USART_SR_TXE))
{
tx_ready = 1;
USARTx->CR1 &= ~USART_CR1_TXEIE;
}
if ((r & USART_SR_RXNE))
{
uint32_t data = USARTx->DR;
/* DR register should be accessed even if data is not used.
* Its read-access has side effect of clearing error flags.
*/
asm volatile ("" : : "r" (data) : "memory");
if ((r & USART_SR_NE))
stat->err_rx_noise++;
else if ((r & USART_SR_FE))
{
stat->rx_break++;
/* XXX: break event report to upper layer? */
}
else if ((r & USART_SR_PE))
stat->err_rx_parity++;
else
{
if ((r & USART_SR_ORE))
stat->err_rx_overrun++;
if (rb_ll_put (rb2a, (data & 0xff)) < 0)
stat->err_rx_overflow++;
}
}
return tx_ready;
}
static int
handle_tx_ready (struct USART *USARTx, struct rng_rb rb2h,
struct usart_stat *stat)
{
int c = rb_ll_get (rb2h);
if (c >= 0)
{
USARTx->DR = c;
USARTx->CR1 |= USART_CR1_TXEIE;
stat->tx++;
return 0;
}
return 1;
}
static void *
usart_main (void *arg)
{
(void)arg;
usart2_tx_ready = 1;
usart3_tx_ready = 1;
chopstx_claim_irq (&usart2_intr, INTR_REQ_USART2);
chopstx_claim_irq (&usart3_intr, INTR_REQ_USART3);
rb_init (&usart2_rb_a2h, buf_usart2_rb_a2h, sizeof buf_usart2_rb_a2h);
rb_init (&usart2_rb_h2a, buf_usart2_rb_h2a, sizeof buf_usart2_rb_h2a);
rb_init (&usart3_rb_a2h, buf_usart3_rb_a2h, sizeof buf_usart3_rb_a2h);
rb_init (&usart3_rb_h2a, buf_usart3_rb_h2a, sizeof buf_usart3_rb_h2a);
rb_get_prepare_poll (&usart2_rb_a2h, &usart2_app_write_event);
rb_get_prepare_poll (&usart3_rb_a2h, &usart3_app_write_event);
while (1)
{
int n = 0;
usart_poll[n++] = &usart2_intr;
usart_poll[n++] = &usart3_intr;
if (usart2_tx_ready)
usart_poll[n++] = &usart2_app_write_event;
else
usart2_app_write_event.ready = 0;
if (usart3_tx_ready)
usart_poll[n++] = &usart3_app_write_event;
else
usart3_app_write_event.ready = 0;
chopstx_poll (NULL, n, usart_poll);
if (usart2_intr.ready)
usart2_tx_ready = handle_intr (USART2, &usart2_rb_h2a, &usart2_stat);
if (usart3_intr.ready)
usart3_tx_ready = handle_intr (USART3, &usart3_rb_h2a, &usart3_stat);
if (usart2_tx_ready && usart2_app_write_event.ready)
usart2_tx_ready = handle_tx_ready (USART2,
&usart2_rb_a2h, &usart2_stat);
if (usart3_tx_ready && usart3_app_write_event.ready)
usart3_tx_ready = handle_tx_ready (USART3,
&usart3_rb_a2h, &usart3_stat);
}
return NULL;
}