82xx serial, smc: add configurable SMC Rx buffer len
This patch adds the configuration option CONFIG_SYS_SMC_RXBUFLEN.
With this option it is possible to allow the receive
buffer for the SMC on 82xx to be greater then 1. In case
CONFIG_SYS_SMC_RXBUFLEN == 1 this driver works as the
old version.
When defining CONFIG_SYS_SMC_RXBUFLEN also
CONFIG_SYS_MAXIDLE must be defined to setup the maximum
idle timeout for the SMC.
Signed-off-by: Heiko Schocher <hs@denx.de>
diff --git a/cpu/mpc8260/serial_smc.c b/cpu/mpc8260/serial_smc.c
index a6efa66..794d6b3 100644
--- a/cpu/mpc8260/serial_smc.c
+++ b/cpu/mpc8260/serial_smc.c
@@ -64,6 +64,23 @@
#endif
+#if !defined(CONFIG_SYS_SMC_RXBUFLEN)
+#define CONFIG_SYS_SMC_RXBUFLEN 1
+#define CONFIG_SYS_MAXIDLE 0
+#else
+#if !defined(CONFIG_SYS_MAXIDLE)
+#error "you must define CONFIG_SYS_MAXIDLE"
+#endif
+#endif
+
+typedef volatile struct serialbuffer {
+ cbd_t rxbd; /* Rx BD */
+ cbd_t txbd; /* Tx BD */
+ uint rxindex; /* index for next character to read */
+ volatile uchar rxbuf[CONFIG_SYS_SMC_RXBUFLEN];/* rx buffers */
+ volatile uchar txbuf; /* tx buffers */
+} serialbuffer_t;
+
/* map rs_table index to baud rate generator index */
static unsigned char brg_map[] = {
6, /* BRG7 for SMC1 */
@@ -79,9 +96,9 @@
volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
volatile smc_t *sp;
volatile smc_uart_t *up;
- volatile cbd_t *tbdf, *rbdf;
volatile cpm8260_t *cp = &(im->im_cpm);
uint dpaddr;
+ volatile serialbuffer_t *rtx;
/* initialize pointers to SMC */
@@ -99,17 +116,21 @@
* damm: allocating space after the two buffers for rx/tx data
*/
- dpaddr = m8260_cpm_dpalloc((2 * sizeof (cbd_t)) + 2, 16);
+ /* allocate size of struct serialbuffer with bd rx/tx,
+ * buffer rx/tx and rx index
+ */
+ dpaddr = m8260_cpm_dpalloc((sizeof(serialbuffer_t)), 16);
+
+ rtx = (serialbuffer_t *)&im->im_dprambase[dpaddr];
/* Set the physical address of the host memory buffers in
* the buffer descriptors.
*/
- rbdf = (cbd_t *)&im->im_dprambase[dpaddr];
- rbdf->cbd_bufaddr = (uint) (rbdf+2);
- rbdf->cbd_sc = 0;
- tbdf = rbdf + 1;
- tbdf->cbd_bufaddr = ((uint) (rbdf+2)) + 1;
- tbdf->cbd_sc = 0;
+ rtx->rxbd.cbd_bufaddr = (uint) &rtx->rxbuf;
+ rtx->rxbd.cbd_sc = 0;
+
+ rtx->txbd.cbd_bufaddr = (uint) &rtx->txbuf;
+ rtx->txbd.cbd_sc = 0;
/* Set up the uart parameters in the parameter ram.
*/
@@ -142,13 +163,13 @@
/* Make the first buffer the only buffer.
*/
- tbdf->cbd_sc |= BD_SC_WRAP;
- rbdf->cbd_sc |= BD_SC_EMPTY | BD_SC_WRAP;
+ rtx->txbd.cbd_sc |= BD_SC_WRAP;
+ rtx->rxbd.cbd_sc |= BD_SC_EMPTY | BD_SC_WRAP;
- /* Single character receive.
- */
- up->smc_mrblr = 1;
- up->smc_maxidl = 0;
+ /* single/multi character receive. */
+ up->smc_mrblr = CONFIG_SYS_SMC_RXBUFLEN;
+ up->smc_maxidl = CONFIG_SYS_MAXIDLE;
+ rtx->rxindex = 0;
/* Initialize Tx/Rx parameters.
*/
@@ -183,27 +204,23 @@
void
serial_putc(const char c)
{
- volatile cbd_t *tbdf;
- volatile char *buf;
volatile smc_uart_t *up;
volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
+ volatile serialbuffer_t *rtx;
if (c == '\n')
serial_putc ('\r');
up = (smc_uart_t *)&(im->im_dprambase[PROFF_SMC]);
- tbdf = (cbd_t *)&im->im_dprambase[up->smc_tbase];
+ rtx = (serialbuffer_t *)&im->im_dprambase[up->smc_rbase];
- /* Wait for last character to go.
- */
- buf = (char *)tbdf->cbd_bufaddr;
- while (tbdf->cbd_sc & BD_SC_READY)
+ /* Wait for last character to go. */
+ while (rtx->txbd.cbd_sc & BD_SC_READY & BD_SC_READY)
;
-
- *buf = c;
- tbdf->cbd_datlen = 1;
- tbdf->cbd_sc |= BD_SC_READY;
+ rtx->txbuf = c;
+ rtx->txbd.cbd_datlen = 1;
+ rtx->txbd.cbd_sc |= BD_SC_READY;
}
void
@@ -217,39 +234,45 @@
int
serial_getc(void)
{
- volatile cbd_t *rbdf;
- volatile unsigned char *buf;
volatile smc_uart_t *up;
volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
- unsigned char c;
+ volatile serialbuffer_t *rtx;
+ unsigned char c;
up = (smc_uart_t *)&(im->im_dprambase[PROFF_SMC]);
- rbdf = (cbd_t *)&im->im_dprambase[up->smc_rbase];
+ rtx = (serialbuffer_t *)&im->im_dprambase[up->smc_rbase];
/* Wait for character to show up.
*/
- buf = (unsigned char *)rbdf->cbd_bufaddr;
- while (rbdf->cbd_sc & BD_SC_EMPTY)
+ while (rtx->rxbd.cbd_sc & BD_SC_EMPTY)
;
- c = *buf;
- rbdf->cbd_sc |= BD_SC_EMPTY;
+ /* the characters are read one by one,
+ * use the rxindex to know the next char to deliver
+ */
+ c = *(unsigned char *) (rtx->rxbd.cbd_bufaddr + rtx->rxindex);
+ rtx->rxindex++;
+
+ /* check if all char are readout, then make prepare for next receive */
+ if (rtx->rxindex >= rtx->rxbd.cbd_datlen) {
+ rtx->rxindex = 0;
+ rtx->rxbd.cbd_sc |= BD_SC_EMPTY;
+ }
return(c);
}
int
serial_tstc()
{
- volatile cbd_t *rbdf;
volatile smc_uart_t *up;
volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
+ volatile serialbuffer_t *rtx;
up = (smc_uart_t *)&(im->im_dprambase[PROFF_SMC]);
+ rtx = (serialbuffer_t *)&im->im_dprambase[up->smc_rbase];
- rbdf = (cbd_t *)&im->im_dprambase[up->smc_rbase];
-
- return(!(rbdf->cbd_sc & BD_SC_EMPTY));
+ return !(rtx->rxbd.cbd_sc & BD_SC_EMPTY);
}
#endif /* CONFIG_CONS_ON_SMC */