KL25Z: Fix serial driver; freedom-kl25z/nsh configuration now works

12 files changed, 166 insertions, 378 deletions

diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index 916e750fc..ada4463bc 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -4619,3 +4619,7 @@
 	  register definitions (2014-4-25).
 	* arch/arm/src/kl/Kconfig, kl_lowputc.c, kl_serial.c, and kl_config.h:
 	  No UART3-5 (2014-4-25).
+	* arch/arm/src/kl/kl_serial.c:  Various fixes to various fils in the
+	  KL architecture directory as need to get the interrupt-driven
+	  serial driver to work.  The Freedom KL25Z NSH configuration now
+	  works (2014-4-25).
diff --git a/nuttx/arch/arm/src/kl/Kconfig b/nuttx/arch/arm/src/kl/Kconfig
index 289387a29..a03a18c2b 100644
--- a/nuttx/arch/arm/src/kl/Kconfig
+++ b/nuttx/arch/arm/src/kl/Kconfig
@@ -414,10 +414,3 @@ config KL_SDHC_DMAPRIO
 		SDHC DMA priority
 
 endif
-
-comment "Kinetis UART Configuration"
-
-config KL_UARTFIFOS
-	bool "Enable UART0 FIFO"
-	default n
-	depends on KL_UART0
diff --git a/nuttx/arch/arm/src/kl/Make.defs b/nuttx/arch/arm/src/kl/Make.defs
index a71160ed0..38c739506 100644
--- a/nuttx/arch/arm/src/kl/Make.defs
+++ b/nuttx/arch/arm/src/kl/Make.defs
@@ -68,8 +68,8 @@ CMN_CSRCS += up_dumpnvic.c
 endif
 
 CHIP_ASRCS  = 
-CHIP_CSRCS  = kl_clockconfig.c kl_gpio.c kl_idle.c kl_irq.c kl_lowputc.c
-CHIP_CSRCS += kl_serial.c kl_start.c kl_timerisr.c kl_cfmconfig.c kl_led.c
+CHIP_CSRCS  = kl_clockconfig.c kl_gpio.c kl_idle.c kl_irq.c kl_irqprio.c
+CHIP_CSRCS += kl_lowputc.c kl_serial.c kl_start.c kl_timerisr.c kl_cfmconfig.c
 
 ifeq ($(CONFIG_NUTTX_KERNEL),y)
 CHIP_CSRCS += kl_userspace.c
diff --git a/nuttx/arch/arm/src/kl/chip/kl_uart.h b/nuttx/arch/arm/src/kl/chip/kl_uart.h
index 40ee713ca..9b0cf80ba 100644
--- a/nuttx/arch/arm/src/kl/chip/kl_uart.h
+++ b/nuttx/arch/arm/src/kl/chip/kl_uart.h
@@ -154,6 +154,7 @@
 #define UART_S1_RDRF                (1 << 5)  /* Bit 5: Receive Data Register Full Flag */
 #define UART_S1_TC                  (1 << 6)  /* Bit 6: Transmit Complete Flag */
 #define UART_S1_TDRE                (1 << 7)  /* Bit 7: Transmit Data Register Empty Flag */
+#define UART_S1_ERRORS              (0x0f)
 
 /* UART Status Register 2 */
 
diff --git a/nuttx/arch/arm/src/kl/kl_config.h b/nuttx/arch/arm/src/kl/kl_config.h
index a76075d68..2344e5eb5 100644
--- a/nuttx/arch/arm/src/kl/kl_config.h
+++ b/nuttx/arch/arm/src/kl/kl_config.h
@@ -97,32 +97,6 @@
 # undef CONFIG_UART1_FLOWCONTROL
 # undef CONFIG_UART2_FLOWCONTROL
 
-/* UART FIFO support is not fully implemented.
- *
- * NOTE:  UART0 has an 8-byte deep FIFO; the other UARTs have no FIFOs
- * (1-deep).  There appears to be no way to know when the FIFO is not
- * full (other than reading the FIFO length and comparing the FIFO count).
- * Hence, the FIFOs are not used in this implementation and, as a result
- * TDRE indeed mean that the single output buffer is available.
- *
- * Performance on UART0 could be improved by enabling the FIFO and by
- * redesigning all of the FIFO status logic.
- */
-
-#undef CONFIG_KL_UARTFIFOS
-
-/* UART Default Interrupt Priorities */
-
-#ifndef CONFIG_KL_UART0PRIO
-#  define CONFIG_KL_UART0PRIO NVIC_SYSH_PRIORITY_DEFAULT
-#endif
-#ifndef CONFIG_KL_UART1PRIO
-#  define CONFIG_KL_UART1PRIO NVIC_SYSH_PRIORITY_DEFAULT
-#endif
-#ifndef CONFIG_KL_UART2PRIO
-#  define CONFIG_KL_UART2PRIO NVIC_SYSH_PRIORITY_DEFAULT
-#endif
-
 /* Ethernet controller configuration */
 
 #ifndef CONFIG_ENET_NRXBUFFERS
diff --git a/nuttx/arch/arm/src/kl/kl_irq.c b/nuttx/arch/arm/src/kl/kl_irq.c
index 783fc42a4..cc2303ae1 100644
--- a/nuttx/arch/arm/src/kl/kl_irq.c
+++ b/nuttx/arch/arm/src/kl/kl_irq.c
@@ -336,72 +336,3 @@ void up_maskack_irq(int irq)
   up_disable_irq(irq);
   kl_clrpend(irq);
 }
-
-/****************************************************************************
- * Name: up_prioritize_irq
- *
- * Description:
- *   Set the priority of an IRQ.
- *
- *   Since this API is not supported on all architectures, it should be
- *   avoided in common implementations where possible.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_ARCH_IRQPRIO
-int up_prioritize_irq(int irq, int priority)
-{
-  uint32_t regaddr;
-  uint32_t regval;
-  int shift;
-
-  DEBUGASSERT(irq == KL_IRQ_SVCALL ||
-              irq == KL_IRQ_PENDSV ||
-              irq == KL_IRQ_SYSTICK ||
-             (irq >= KL_IRQ_EXTINT && irq < NR_IRQS));
-  DEBUGASSERT(priority >= NVIC_SYSH_PRIORITY_MAX &&
-              priority <= NVIC_SYSH_PRIORITY_MIN);
-
-  /* Check for external interrupt */
-
-  if (irq >= KL_IRQ_EXTINT && irq < (KL_IRQ_EXTINT + 32))
-    {
-      /* ARMV6M_NVIC_IPR() maps register IPR0-IPR7 with four settings per
-       * register.
-       */
-
-      regaddr = ARMV6M_NVIC_IPR(irq >> 2);
-      shift   = (irq & 3) << 3;
-    }
-
-  /* Handle processor exceptions.  Only SVCall, PendSV, and SysTick can be
-   * reprioritized.  And we will not permit modification of SVCall through
-   * this function.
-   */
-
-  else if (irq == KL_IRQ_PENDSV)
-    {
-      regaddr = ARMV6M_SYSCON_SHPR2;
-      shift   = SYSCON_SHPR3_PRI_14_SHIFT;
-    }
-  else if (irq == KL_IRQ_SYSTICK)
-    {
-      regaddr = ARMV6M_SYSCON_SHPR2;
-      shift   = SYSCON_SHPR3_PRI_15_SHIFT;
-    }
-  else
-    {
-      return ERROR;
-    }
-
-  /* Set the priority */
-
-  regval  = getreg32(regaddr);
-  regval &= ~((uint32_t)0xff << shift);
-  regval |= ((uint32_t)priority << shift);
-  putreg32(regval, regaddr);
-
-  kl_dumpnvic("prioritize", irq);
-  return OK;
-}
-#endif
diff --git a/nuttx/arch/arm/src/kl/kl_irqprio.c b/nuttx/arch/arm/src/kl/kl_irqprio.c
new file mode 100644
index 000000000..17611aeea
--- /dev/null
+++ b/nuttx/arch/arm/src/kl/kl_irqprio.c
@@ -0,0 +1,127 @@
+/****************************************************************************
+ * arch/arm/src/stm32/kl_irqprio.c
+ * arch/arm/src/chip/kl_irqprio.c
+ *
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <assert.h>
+#include <arch/irq.h>
+
+#include "nvic.h"
+#include "up_arch.h"
+
+#include "kl_irq.h"
+
+#ifdef CONFIG_ARCH_IRQPRIO
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+int up_prioritize_irq(int irq, int priority)
+{
+  uint32_t regaddr;
+  uint32_t regval;
+  int shift;
+
+  DEBUGASSERT(irq == KL_IRQ_SVCALL ||
+              irq == KL_IRQ_PENDSV ||
+              irq == KL_IRQ_SYSTICK ||
+             (irq >= KL_IRQ_EXTINT && irq < NR_IRQS));
+  DEBUGASSERT(priority >= NVIC_SYSH_PRIORITY_MAX &&
+              priority <= NVIC_SYSH_PRIORITY_MIN);
+
+  /* Check for external interrupt */
+
+  if (irq >= KL_IRQ_EXTINT && irq < (KL_IRQ_EXTINT + 32))
+    {
+      /* ARMV6M_NVIC_IPR() maps register IPR0-IPR7 with four settings per
+       * register.
+       */
+
+      regaddr = ARMV6M_NVIC_IPR(irq >> 2);
+      shift   = (irq & 3) << 3;
+    }
+
+  /* Handle processor exceptions.  Only SVCall, PendSV, and SysTick can be
+   * reprioritized.  And we will not permit modification of SVCall through
+   * this function.
+   */
+
+  else if (irq == KL_IRQ_PENDSV)
+    {
+      regaddr = ARMV6M_SYSCON_SHPR2;
+      shift   = SYSCON_SHPR3_PRI_14_SHIFT;
+    }
+  else if (irq == KL_IRQ_SYSTICK)
+    {
+      regaddr = ARMV6M_SYSCON_SHPR2;
+      shift   = SYSCON_SHPR3_PRI_15_SHIFT;
+    }
+  else
+    {
+      return ERROR;
+    }
+
+  /* Set the priority */
+
+  regval  = getreg32(regaddr);
+  regval &= ~((uint32_t)0xff << shift);
+  regval |= ((uint32_t)priority << shift);
+  putreg32(regval, regaddr);
+  return OK;
+}
+#endif
diff --git a/nuttx/arch/arm/src/kl/kl_led.c b/nuttx/arch/arm/src/kl/kl_led.c
deleted file mode 100644
index 3f2c36f02..000000000
--- a/nuttx/arch/arm/src/kl/kl_led.c
+++ /dev/null
@@ -1,28 +0,0 @@
-void blueled(int on)
-{
-  volatile unsigned int *SIM_COPC = ((volatile unsigned int *)0x40048100);
-  volatile unsigned int *SIM_SCGC5 = ((volatile unsigned int *)0x40048038);
-  volatile unsigned int *PORTD_PCR1 = ((volatile unsigned int *)0x4004C004);
-  volatile unsigned int *GPIOD_PSOR = ((volatile unsigned int *)0x400FF0C4);
-  volatile unsigned int *GPIOD_PCOR = ((volatile unsigned int *)0x400FF0C8);
-  volatile unsigned int *GPIOD_PDDR = ((volatile unsigned int *)0x400FF0D4);
-
-  /*acassis: disable SIM_COP*/
-  *SIM_COPC = 0;
-
-  /* enable clocks for PORTD */
-  *SIM_SCGC5 = 0x1000;
-
-  /* set D1 to GPIO */
-  *PORTD_PCR1 = 0x100;
-
-  /* set D1 DDR to output */
-  *GPIOD_PDDR |= 2;
-
-  if(on)
-    *GPIOD_PCOR = 2;
-  else
-      *GPIOD_PSOR = 2;
-
-}
-
diff --git a/nuttx/arch/arm/src/kl/kl_lowputc.c b/nuttx/arch/arm/src/kl/kl_lowputc.c
index d9d3604e1..5f2242969 100644
--- a/nuttx/arch/arm/src/kl/kl_lowputc.c
+++ b/nuttx/arch/arm/src/kl/kl_lowputc.c
@@ -99,14 +99,6 @@
  * Private Variables
  **************************************************************************/
 
-/* This array maps an encoded FIFO depth (index) to the actual size of the
- * FIFO (indexed value).  NOTE:  That there is no 8th value.
- */
-
-#ifdef CONFIG_KL_UARTFIFOS
-static uint8_t g_sizemap[8] = {1, 4, 8, 16, 32, 64, 128, 0};
-#endif
-
 /**************************************************************************
  * Private Functions
  **************************************************************************/
@@ -126,15 +118,6 @@ static uint8_t g_sizemap[8] = {1, 4, 8, 16, 32, 64, 128, 0};
 void kl_lowputc(uint32_t ch)
 {
 #if defined HAVE_UART_DEVICE && defined HAVE_SERIAL_CONSOLE
-#ifdef CONFIG_KL_UARTFIFOS
-  /* Wait until there is space in the TX FIFO:  Read the number of bytes
-   * currently in the FIFO and compare that to the size of the FIFO.  If
-   * there are fewer bytes in the FIFO than the size of the FIFO, then we
-   * are able to transmit.
-   */
-
-#  error "Missing logic"
-#else
   /* Wait until the transmit data register is "empty" (TDRE).  This state
    * depends on the TX watermark setting and may not mean that the transmit
    * buffer is truly empty.  It just means that we can now add another
@@ -152,8 +135,6 @@ void kl_lowputc(uint32_t ch)
 
   while ((getreg8(CONSOLE_BASE+KL_UART_S1_OFFSET) & UART_S1_TDRE) == 0);
 
-#endif
-
  /* Then write the character to the UART data register */
 
   putreg8((uint8_t)ch, CONSOLE_BASE+KL_UART_D_OFFSET);
@@ -272,9 +253,6 @@ void kl_uartconfigure(uintptr_t uart_base, uint32_t baud, uint32_t clock,
   uint32_t     sbr;
   uint32_t     tmp;
   uint8_t      regval;
-#ifdef CONFIG_KL_UARTFIFOS
-  unsigned int depth;
-#endif
 
   /* Disable the transmitter and receiver throughout the reconfiguration */
 
diff --git a/nuttx/arch/arm/src/kl/kl_serial.c b/nuttx/arch/arm/src/kl/kl_serial.c
index 3aa5a9ad9..d4f37f9f2 100644
--- a/nuttx/arch/arm/src/kl/kl_serial.c
+++ b/nuttx/arch/arm/src/kl/kl_serial.c
@@ -158,11 +158,7 @@ struct up_dev_s
   uintptr_t uartbase;  /* Base address of UART registers */
   uint32_t  baud;      /* Configured baud */
   uint32_t  clock;     /* Clocking frequency of the UART module */
-#ifdef CONFIG_DEBUG
-  uint8_t   irqe;      /* Error IRQ associated with this UART (for enable) */
-#endif
-  uint8_t   irqs;      /* Status IRQ associated with this UART (for enable) */
-  uint8_t   irqprio;   /* Interrupt priority */
+  uint8_t   irq;       /* IRQ associated with this UART (for enable) */
   uint8_t   ie;        /* Interrupts enabled */
   uint8_t   parity;    /* 0=none, 1=odd, 2=even */
   uint8_t   bits;      /* Number of bits (8 or 9) */
@@ -176,9 +172,6 @@ static int  up_setup(struct uart_dev_s *dev);
 static void up_shutdown(struct uart_dev_s *dev);
 static int  up_attach(struct uart_dev_s *dev);
 static void up_detach(struct uart_dev_s *dev);
-#ifdef CONFIG_DEBUG
-static int  up_interrupte(int irq, void *context);
-#endif
 static int  up_interrupts(int irq, void *context);
 static int  up_ioctl(struct file *filep, int cmd, unsigned long arg);
 static int  up_receive(struct uart_dev_s *dev, uint32_t *status);
@@ -187,9 +180,6 @@ static bool up_rxavailable(struct uart_dev_s *dev);
 static void up_send(struct uart_dev_s *dev, int ch);
 static void up_txint(struct uart_dev_s *dev, bool enable);
 static bool up_txready(struct uart_dev_s *dev);
-#ifdef CONFIG_KL_UARTFIFOS
-static bool up_txempty(struct uart_dev_s *dev);
-#endif
 
 /****************************************************************************
  * Private Variables
@@ -208,11 +198,7 @@ static const struct uart_ops_s g_uart_ops =
   .send           = up_send,
   .txint          = up_txint,
   .txready        = up_txready,
-#ifdef CONFIG_KL_UARTFIFOS
-  .txempty        = up_txempty,
-#else
   .txempty        = up_txready,
-#endif
 };
 
 /* I/O buffers */
@@ -238,7 +224,7 @@ static struct up_dev_s g_uart0priv =
   .uartbase       = KL_UART0_BASE,
   .clock          = BOARD_CORECLK_FREQ,
   .baud           = CONFIG_UART0_BAUD,
-  .irqprio        = CONFIG_KL_UART0PRIO,
+  .irq            = KL_IRQ_UART0,
   .parity         = CONFIG_UART0_PARITY,
   .bits           = CONFIG_UART0_BITS,
 };
@@ -268,11 +254,7 @@ static struct up_dev_s g_uart1priv =
   .uartbase       = KL_UART1_BASE,
   .clock          = BOARD_BUSCLK_FREQ,
   .baud           = CONFIG_UART1_BAUD,
-#ifdef CONFIG_DEBUG
-  .irqe           = KL_IRQ_UART1E,
-#endif
-  .irqs           = KL_IRQ_UART1S,
-  .irqprio        = CONFIG_KL_UART1PRIO,
+  .irq            = KL_IRQ_UART1,
   .parity         = CONFIG_UART1_PARITY,
   .bits           = CONFIG_UART1_BITS,
 };
@@ -302,11 +284,7 @@ static struct up_dev_s g_uart2priv =
   .uartbase       = KL_UART2_BASE,
   .clock          = BOARD_BUSCLK_FREQ,
   .baud           = CONFIG_UART2_BAUD,
-#ifdef CONFIG_DEBUG
-  .irqe           = KL_IRQ_UART2E,
-#endif
-  .irqs           = KL_IRQ_UART2S,
-  .irqprio        = CONFIG_KL_UART2PRIO,
+  .irq            = KL_IRQ_UART2,
   .parity         = CONFIG_UART2_PARITY,
   .bits           = CONFIG_UART2_BITS,
 };
@@ -426,13 +404,6 @@ static int up_setup(struct uart_dev_s *dev)
   /* Make sure that all interrupts are disabled */
 
   up_restoreuartint(priv, 0);
-
-  /* Set up the interrupt priority */
-
-  up_prioritize_irq(priv->irqs, priv->irqprio);
-#ifdef CONFIG_DEBUG
-  up_prioritize_irq(priv->irqe, priv->irqprio);
-#endif
   return OK;
 }
 
@@ -482,20 +453,10 @@ static int up_attach(struct uart_dev_s *dev)
    * disabled in the C2 register.
    */
 
-  ret = irq_attach(priv->irqs, up_interrupts);
-#ifdef CONFIG_DEBUG
+  ret = irq_attach(priv->irq, up_interrupts);
   if (ret == OK)
     {
-      ret = irq_attach(priv->irqe, up_interrupte);
-    }
-#endif
-
-  if (ret == OK)
-    {
-#ifdef CONFIG_DEBUG
-      up_enable_irq(priv->irqe);
-#endif
-      up_enable_irq(priv->irqs);
+      up_enable_irq(priv->irq);
     }
 
   return ret;
@@ -518,78 +479,12 @@ static void up_detach(struct uart_dev_s *dev)
   /* Disable interrupts */
 
   up_restoreuartint(priv, 0);
-#ifdef CONFIG_DEBUG
-  up_disable_irq(priv->irqe);
-#endif
-  up_disable_irq(priv->irqs);
+  up_disable_irq(priv->irq);
 
   /* Detach from the interrupt(s) */
 
-  irq_detach(priv->irqs);
-#ifdef CONFIG_DEBUG
-  irq_detach(priv->irqe);
-#endif
-}
-
-/****************************************************************************
- * Name: up_interrupte
- *
- * Description:
- *   This is the UART error interrupt handler.  It will be invoked when an
- *   interrupt received on the 'irq'
- *
- ****************************************************************************/
-
-#ifdef CONFIG_DEBUG
-static int up_interrupte(int irq, void *context)
-{
-  struct uart_dev_s *dev = NULL;
-  struct up_dev_s   *priv;
-  uint8_t            regval;
-
-#ifdef CONFIG_KL_UART0
-  if (g_uart0priv.irqe == irq)
-    {
-      dev = &g_uart0port;
-    }
-  else
-#endif
-#ifdef CONFIG_KL_UART1
-  if (g_uart1priv.irqe == irq)
-    {
-      dev = &g_uart1port;
-    }
-  else
-#endif
-#ifdef CONFIG_KL_UART2
-  if (g_uart2priv.irqe == irq)
-    {
-      dev = &g_uart2port;
-    }
-  else
-#endif
-    {
-      PANIC(OSERR_INTERNAL);
-    }
-  priv = (struct up_dev_s*)dev->priv;
-  DEBUGASSERT(priv);
-
-  /* Handle error interrupts.  This interrupt may be caused by:
-   *
-   * FE: Framing error. To clear FE, read S1 with FE set and then read the
-   *     UART data register (D).
-   * NF: Noise flag. To clear NF, read S1 and then read the UART data
-   *     register (D).
-   * PF: Parity error flag. To clear PF, read S1 and then read the UART data
-   *     register (D).
-   */
-
-  regval = up_serialin(priv, KL_UART_S1_OFFSET);
-  lldbg("S1: %02x\n", regval);
-  regval = up_serialin(priv, KL_UART_D_OFFSET);
-  return OK;
+  irq_detach(priv->irq);
 }
-#endif /* CONFIG_DEBUG */
 
 /****************************************************************************
  * Name: up_interrupts
@@ -608,29 +503,25 @@ static int up_interrupts(int irq, void *context)
   struct uart_dev_s *dev = NULL;
   struct up_dev_s   *priv;
   int                passes;
-#ifdef CONFIG_KL_UARTFIFOS
-  unsigned int       count;
-#else
   uint8_t            s1;
-#endif
   bool               handled;
 
 #ifdef CONFIG_KL_UART0
-  if (g_uart0priv.irqs == irq)
+  if (g_uart0priv.irq == irq)
     {
       dev = &g_uart0port;
     }
   else
 #endif
 #ifdef CONFIG_KL_UART1
-  if (g_uart1priv.irqs == irq)
+  if (g_uart1priv.irq == irq)
     {
       dev = &g_uart1port;
     }
   else
 #endif
 #ifdef CONFIG_KL_UART2
-  if (g_uart2priv.irqs == irq)
+  if (g_uart2priv.irq == irq)
     {
       dev = &g_uart2port;
     }
@@ -653,18 +544,8 @@ static int up_interrupts(int irq, void *context)
 
       /* Read status register 1 */
 
-#ifndef CONFIG_KL_UARTFIFOS
       s1 = up_serialin(priv, KL_UART_S1_OFFSET);
-#endif
-
-      /* Handle incoming, receive bytes */
-
-#ifdef CONFIG_KL_UARTFIFOS
-      /* Check the count of bytes in the RX FIFO */
 
-      count = up_serialin(priv, KL_UART_RCFIFO_OFFSET);
-      if (count > 0)
-#else
       /* Check if the receive data register is full (RDRF).  NOTE:  If
        * FIFOS are enabled, this does not mean that the the FIFO is full,
        * rather, it means that the the number of bytes in the RX FIFO has
@@ -676,7 +557,6 @@ static int up_interrupts(int irq, void *context)
        */
 
       if ((s1 & UART_S1_RDRF) != 0)
-#endif
         {
           /* Process incoming bytes */
 
@@ -686,14 +566,6 @@ static int up_interrupts(int irq, void *context)
 
       /* Handle outgoing, transmit bytes */
 
-#ifdef CONFIG_KL_UARTFIFOS
-      /* Read the number of bytes currently in the FIFO and compare that to
-       * the size of the FIFO.  If there are fewer bytes in the FIFO than
-       * the size of the FIFO, then we are able to transmit.
-       */
-
-#  error "Missing logic"
-#else
       /* Check if the transmit data register is "empty."  NOTE:  If FIFOS
        * are enabled, this does not mean that the the FIFO is empty, rather,
        * it means that the the number of bytes in the TX FIFO is below the
@@ -705,13 +577,25 @@ static int up_interrupts(int irq, void *context)
        */
 
       if ((s1 & UART_S1_TDRE) != 0)
-#endif
         {
           /* Process outgoing bytes */
 
           uart_xmitchars(dev);
           handled = true;
         }
+
+      /* Handle error interrupts.  This interrupt may be caused by:
+       *
+       * FE: Framing error. To clear FE, write a logic one to the FE flag.
+       * NF: Noise flag. To clear NF, write logic one to the NF.
+       * PF: Parity error flag. To clear PF, write a logic one to the PF.
+       * OR: Receiver Overrun Flag.  To clear OR, write a logic 1 to the OR flag.
+       */
+
+       if ((s1 & UART_S1_ERRORS) != 0)
+         {
+           up_serialout(priv, KL_UART_S1_OFFSET, (s1 & UART_S1_ERRORS));
+         }
     }
 
   return OK;
@@ -824,12 +708,7 @@ static void up_rxint(struct uart_dev_s *dev, bool enable)
     }
   else
     {
-#ifdef CONFIG_DEBUG
-#  warning "Revisit:  How are errors enabled?"
-      priv->ie |= UART_C2_RIE;
-#else
       priv->ie |= UART_C2_RIE;
-#endif
       up_setuartint(priv);
     }
 
@@ -847,14 +726,7 @@ static void up_rxint(struct uart_dev_s *dev, bool enable)
 static bool up_rxavailable(struct uart_dev_s *dev)
 {
   struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
-#ifdef CONFIG_KL_UARTFIFOS
-  unsigned int count;
 
-  /* Return true if there are any bytes in the RX FIFO */
-
-  count = up_serialin(priv, KL_UART_RCFIFO_OFFSET);
-  return count > 0;
-#else
   /* Return true if the receive data register is full (RDRF).  NOTE:  If
    * FIFOS are enabled, this does not mean that the the FIFO is full,
    * rather, it means that the the number of bytes in the RX FIFO has
@@ -863,7 +735,6 @@ static bool up_rxavailable(struct uart_dev_s *dev)
    */
 
   return (up_serialin(priv, KL_UART_S1_OFFSET) & UART_S1_RDRF) != 0;
-#endif
 }
 
 /****************************************************************************
@@ -932,14 +803,6 @@ static bool up_txready(struct uart_dev_s *dev)
 {
   struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
 
-#ifdef CONFIG_KL_UARTFIFOS
-  /* Read the number of bytes currently in the FIFO and compare that to the
-   * size of the FIFO.  If there are fewer bytes in the FIFO than the size
-   * of the FIFO, then we are able to transmit.
-   */
-
-#  error "Missing logic"
-#else
   /* Return true if the transmit data register is "empty."  NOTE:  If
    * FIFOS are enabled, this does not mean that the the FIFO is empty,
    * rather, it means that the the number of bytes in the TX FIFO is
@@ -948,29 +811,9 @@ static bool up_txready(struct uart_dev_s *dev)
    */
 
   return (up_serialin(priv, KL_UART_S1_OFFSET) & UART_S1_TDRE) != 0;
-#endif
 }
 
 /****************************************************************************
- * Name: up_txempty
- *
- * Description:
- *   Return true if the tranmsit data register is empty
- *
- ****************************************************************************/
-
-#ifdef CONFIG_KL_UARTFIFOS
-static bool up_txempty(struct uart_dev_s *dev)
-{
-  struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
-
-  /* Return true if the transmit buffer/fifo is "empty." */
-
-  return (up_serialin(priv, KL_UART_SFIFO_OFFSET) & UART_SFIFO_TXEMPT) != 0;
-}
-#endif
-
-/****************************************************************************
  * Public Functions
  ****************************************************************************/
 
diff --git a/nuttx/arch/arm/src/kl/kl_start.c b/nuttx/arch/arm/src/kl/kl_start.c
index decd934a0..be45a688d 100644
--- a/nuttx/arch/arm/src/kl/kl_start.c
+++ b/nuttx/arch/arm/src/kl/kl_start.c
@@ -50,6 +50,8 @@
 #include "up_arch.h"
 #include "up_internal.h"
 
+#include "chip/kl_sim.h"
+
 #include "kl_config.h"
 #include "kl_lowputc.h"
 #include "kl_userspace.h"
@@ -102,14 +104,6 @@ const uint32_t g_idle_topstack = IDLE_STACK;
  * Public Functions
  ****************************************************************************/
 
-void iprintf(const char *string)
-{
-  while(*string != '\0')
-    {
-      kl_lowputc((char) *string++);
-    }
-}
-
 /****************************************************************************
  * Name: _start
  *
@@ -122,23 +116,17 @@ void __start(void)
 {
   const uint32_t *src;
   uint32_t *dest;
-  volatile unsigned int *SIM_COPC = ((volatile unsigned int *)0x40048100);
-  //int i = 0;
 
-  /*acassis: disable SIM_COP*/
-  *SIM_COPC = 0;
+  /* Disable the watchdog */
+
+  putreg32(0, KL_SIM_COPC);
 
   /* Configure the uart so that we can get debug output as soon as possible */
 
   kl_clockconfig();
   kl_lowsetup();
-  //uart_init();
   showprogress('A');
 
-  /* Blink blue LED to indicate we are here */
-  //for (; ; i++)
-  //    blueled(i & 0x10000);
-
   /* Clear .bss.  We'll do this inline (vs. calling memset) just to be
    * certain that there are no issues with the state of global variables.
    */
@@ -186,12 +174,8 @@ void __start(void)
 
   /* Then start NuttX */
 
-  //iprintf("\r\nWelcome to NuttX!\r\n");
-
-  //showprogress('\r');
-  //showprogress('\n');
-
-  iprintf("\r\n\r\n");
+  showprogress('\r');
+  showprogress('\n');
 
   os_start();
 
diff --git a/nuttx/configs/freedom-kl25z/ostest/defconfig b/nuttx/configs/freedom-kl25z/ostest/defconfig
index 9a7491efe..442487f3e 100644
--- a/nuttx/configs/freedom-kl25z/ostest/defconfig
+++ b/nuttx/configs/freedom-kl25z/ostest/defconfig
@@ -38,28 +38,10 @@ CONFIG_RAW_BINARY=y
 #
 # Debug Options
 #
-CONFIG_DEBUG=y
+# CONFIG_DEBUG is not set
 # CONFIG_DEBUG_VERBOSE is not set
 
 #
-# Subsystem Debug Options
-#
-# CONFIG_DEBUG_MM is not set
-CONFIG_DEBUG_SCHED=y
-# CONFIG_DEBUG_FS is not set
-# CONFIG_DEBUG_LIB is not set
-# CONFIG_DEBUG_BINFMT is not set
-# CONFIG_DEBUG_GRAPHICS is not set
-
-#
-# Driver Debug Options
-#
-# CONFIG_DEBUG_LEDS is not set
-# CONFIG_DEBUG_ANALOG is not set
-# CONFIG_DEBUG_GPIO is not set
-# CONFIG_DEBUG_SYMBOLS is not set
-
-#
 # System Type
 #
 # CONFIG_ARCH_8051 is not set
@@ -235,7 +217,6 @@ CONFIG_TASK_NAME_SIZE=0
 CONFIG_SCHED_HAVE_PARENT=y
 CONFIG_SCHED_CHILD_STATUS=y
 CONFIG_PREALLOC_CHILDSTATUS=0
-# CONFIG_DEBUG_CHILDSTATUS is not set
 # CONFIG_JULIAN_TIME is not set
 CONFIG_START_YEAR=2013
 CONFIG_START_MONTH=2