Get some basic Teensy code working

It prints some stuff over the USB serial port and turns the on-board LED
on. Also tweak some of the existing code so it works with better
compiler options for what we're doing.

Change-Id: Ifcbd36f9eaca47a86f7a97e8c458c64f9b3df3ab
diff --git a/motors/util.h b/motors/util.h
new file mode 100644
index 0000000..05edd9d
--- /dev/null
+++ b/motors/util.h
@@ -0,0 +1,154 @@
+#ifndef MOTORS_UTIL_H_
+#define MOTORS_UTIL_H_
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+// The GPIO bitband register for a specific bit of a given GPIO register.
+//
+// reg really must be one of the GPIO module's addresses
+// (0x400FF000 - 0x400FFFFF).
+#define GPIO_BITBAND(reg, bit)                                             \
+  (*(volatile uint32_t *)(((uint32_t) & (reg)-0x40000000) * 32 + (bit)*4 + \
+                          0x42000000))
+
+#define NVIC_SET_SANE_PRIORITY(irqnum, priority) \
+  NVIC_SET_PRIORITY(irqnum, ((priority)&0xF) << 4)
+#define NVIC_GET_SANE_PRIORITY(irqnum) (NVIC_GET_PRIORITY(irqnum) >> 4)
+
+// Definitions for the bits in some registers that are missing.
+#define CAN_MCR_MDIS ((uint32_t)(1 << 31))
+#define CAN_MCR_FRZ ((uint32_t)(1 << 30))
+#define CAN_MCR_RFEN ((uint32_t)(1 << 29))
+#define CAN_MCR_HALT ((uint32_t)(1 << 28))
+#define CAN_MCR_NOTRDY ((uint32_t)(1 << 27))
+#define CAN_MCR_WAKMSK ((uint32_t)(1 << 26))
+#define CAN_MCR_SOFTRST ((uint32_t)(1 << 25))
+#define CAN_MCR_FRZACK ((uint32_t)(1 << 24))
+#define CAN_MCR_SUPV ((uint32_t)(1 << 23))
+#define CAN_MCR_SLFWAK ((uint32_t)(1 << 22))
+#define CAN_MCR_WRNEN ((uint32_t)(1 << 21))
+#define CAN_MCR_LPMACK ((uint32_t)(1 << 20))
+#define CAN_MCR_WAKSRC ((uint32_t)(1 << 19))
+#define CAN_MCR_SRXDIS ((uint32_t)(1 << 17))
+#define CAN_MCR_IRMQ ((uint32_t)(1 << 16))
+#define CAN_MCR_LPRIOEN ((uint32_t)(1 << 13))
+#define CAN_MCR_AEN ((uint32_t)(1 << 12))
+#define CAN_MCR_IDAM(n) ((uint32_t)(((n) & 3) << 8))
+#define CAN_MCR_MAXMB(n) ((uint32_t)((n) & 0x7F))
+#define CAN_CTRL1_PRESDIV(n) ((uint32_t)(((n) & 0xFF) << 24))
+#define CAN_CTRL1_RJW(n) ((uint32_t)(((n) & 3) << 22))
+#define CAN_CTRL1_PSEG1(n) ((uint32_t)(((n) & 7) << 19))
+#define CAN_CTRL1_PSEG2(n) ((uint32_t)(((n) & 7) << 16))
+#define CAN_CTRL1_BOFFMSK ((uint32_t)(1 << 15))
+#define CAN_CTRL1_ERRMSK ((uint32_t)(1 << 14))
+#define CAN_CTRL1_CLKSRC ((uint32_t)(1 << 13))
+#define CAN_CTRL1_LPB ((uint32_t)(1 << 12))
+#define CAN_CTRL1_TWRNMSK ((uint32_t)((1 << 11))
+#define CAN_CTRL1_RWRNMSK ((uint32_t)((1 << 10))
+#define CAN_CTRL1_SMP ((uint32_t)(1 << 7))
+#define CAN_CTRL1_BOFFREC ((uint32_t)(1 << 6)
+#define CAN_CTRL1_TSYN ((uint32_t)(1 << 5))
+#define CAN_CTRL1_LBUF ((uint32_t)(1 << 4))
+#define CAN_CTRL1_LOM ((uint32_t)(1 << 3))
+#define CAN_CTRL1_PROPSEG(n) ((uint32_t)((n) & 7))
+#define CAN_ESR1_SYNCH ((uint32_t)(1 << 18))
+#define CAN_ESR1_TWRNINT ((uint32_t)(1 << 17))
+#define CAN_ESR1_RWRNINT ((uint32_t)(1 << 16))
+#define CAN_ESR1_BIT1ERR ((uint32_t)(1 << 15))
+#define CAN_ESR1_BIT0ERR ((uint32_t)(1 << 14))
+#define CAN_ESR1_ACKERR ((uint32_t)(1 << 13))
+#define CAN_ESR1_CRCERR ((uint32_t)(1 << 12))
+#define CAN_ESR1_FRMERR ((uint32_t)(1 << 11))
+#define CAN_ESR1_STFERR ((uint32_t)(1 << 10))
+#define CAN_ESR1_TXWRN ((uint32_t)(1 << 9))
+#define CAN_ESR1_RXWRN ((uint32_t)(1 << 8))
+#define CAN_ESR1_IDLE ((uint32_t)(1 << 7))
+#define CAN_ESR1_TX ((uint32_t)(1 << 6))
+#define CAN_ESR1_RX ((uint32_t)(1 << 3))
+#define CAN_ESR1_BOFFINT ((uint32_t)(1 << 2))
+#define CAN_ESR1_ERRINT ((uint32_t)(1 << 1))
+#define CAN_ESR1_WAKINT ((uint32_t)1)
+#define CAN_CTRL2_WRMFRZ ((uint32_t)(1 << 28))
+#define CAN_CTRL2_RFFN(n) ((uint32_t)(((n) & 0xF) << 24))
+#define CAN_CTRL2_TASD(n) ((uint32_t)(((n) & 0x1F) << 19))
+#define CAN_CTRL2_MRP ((uint32_t)(1 << 18))
+#define CAN_CTRL2_RRS ((uint32_t)(1 << 17))
+#define CAN_CTRL2_EACEN ((uint32_t)(1 << 16))
+#define CAN_ESR2_VPS ((uint32_t)(1 << 14))
+#define CAN_ESR2_IMB ((uint32_t)(1 << 13))
+
+typedef struct {
+  // Timestamp is the lower 16 bits.
+  uint32_t control_timestamp;
+  uint32_t prio_id;
+  uint32_t data[2];
+} CanMessageBuffer;
+#define CAN0_MESSAGES ((volatile CanMessageBuffer *)0x40024080)
+#define CAN0_RXIMRS ((volatile uint32_t *)0x40024880)
+#define CAN1_MESSAGES ((volatile CanMessageBuffer *)0x400A4080)
+#define CAN1_RXIMRS ((volatile uint32_t *)0x400A4880)
+#define CAN_MB_CONTROL_INSERT_DLC(dlc) ((uint32_t)(((dlc) & 0xF) << 16))
+#define CAN_MB_CONTROL_EXTRACT_DLC(control_timestamp) \
+  ((control_timestamp >> 16) & 0xF)
+#define CAN_MB_CONTROL_RTR ((uint32_t)(1 << 20))
+#define CAN_MB_CONTROL_IDE ((uint32_t)(1 << 21))
+#define CAN_MB_CONTROL_SRR ((uint32_t)(1 << 22))
+#define CAN_MB_CONTROL_INSERT_CODE(n) ((uint32_t)(((n) & 0xF) << 24))
+#define CAN_MB_CONTROL_CODE_BUSY_MASK CAN_MB_CONTROL_INSERT_CODE(1)
+#define CAN_MB_PRIO_ID_PRIORITY_MASK ((uint32_t)((1 << 29) - 1))
+#define CAN_MB_CODE_RX_INACTIVE 0
+#define CAN_MB_CODE_RX_EMPTY 4
+#define CAN_MB_CODE_RX_FULL 2
+#define CAN_MB_CODE_RX_OVERRUN 6
+#define CAN_MB_CODE_RX_RANSWER 0xA
+#define CAN_MB_CODE_TX_INACTIVE 8
+#define CAN_MB_CODE_TX_ABORT 9
+#define CAN_MB_CODE_TX_DATA 0xC
+#define CAN_MB_CODE_TX_REMOTE 0xC
+#define CAN_MB_CODE_TX_TANSWER 0xE
+#define CAN_MB_CODE_IS_BUSY(code) ((code) & 1)
+
+// We have to define these, and leave them defined, because the C preprocessor
+// is annoying...
+#define REALLY_DO_CONCATENATE(x, y, z) x ## y ## z
+#define DO_CONCATENATE(x, y, z) REALLY_DO_CONCATENATE(x, y, z)
+
+// Index-parameterized access to various registers from various peripherals.
+// This only includes ones somebody thought might be useful; add more if you
+// want them.
+#define DMA_TCDn_SADDR(n) DO_CONCATENATE(DMA_TCD, n, _SADDR)
+#define DMA_TCDn_SOFF(n) DO_CONCATENATE(DMA_TCD, n, _SOFF)
+#define DMA_TCDn_ATTR(n) DO_CONCATENATE(DMA_TCD, n, _ATTR)
+#define DMA_TCDn_NBYTES_MLNO(n) DO_CONCATENATE(DMA_TCD, n, _NBYTES_MLNO)
+#define DMA_TCDn_NBYTES_MLOFFNO(n) DO_CONCATENATE(DMA_TCD, n, _NBYTES_MLOFFNO)
+#define DMA_TCDn_NBYTES_MLOFFYES(n) DO_CONCATENATE(DMA_TCD, n, _NBYTES_MLOFFYES)
+#define DMA_TCDn_SLAST(n) DO_CONCATENATE(DMA_TCD, n, _SLAST)
+#define DMA_TCDn_DADDR(n) DO_CONCATENATE(DMA_TCD, n, _DADDR)
+#define DMA_TCDn_DOFF(n) DO_CONCATENATE(DMA_TCD, n, _DOFF)
+#define DMA_TCDn_CITER_ELINKYES(n) DO_CONCATENATE(DMA_TCD, n, _CITER_ELINKYES)
+#define DMA_TCDn_CITER_ELINKNO(n) DO_CONCATENATE(DMA_TCD, n, _CITER_ELINKNO)
+#define DMA_TCDn_DLASTSGA(n) DO_CONCATENATE(DMA_TCD, n, _DLASTSGA)
+#define DMA_TCDn_CSR(n) DO_CONCATENATE(DMA_TCD, n, _CSR)
+#define DMA_TCDn_BITER_ELINKYES(n) DO_CONCATENATE(DMA_TCD, n, _BITER_ELINKYES)
+#define DMA_TCDn_BITER_ELINKNO(n) DO_CONCATENATE(DMA_TCD, n, _BITER_ELINKNO)
+#define SPIn_MCR(n) DO_CONCATENATE(SPI, n, _MCR)
+#define SPIn_TCR(n) DO_CONCATENATE(SPI, n, _TCR)
+#define SPIn_CTAR0(n) DO_CONCATENATE(SPI, n, _CTAR0)
+#define SPIn_SR(n) DO_CONCATENATE(SPI, n, _SR)
+#define SPIn_RSER(n) DO_CONCATENATE(SPI, n, _RSER)
+#define SPIn_PUSHR(n) DO_CONCATENATE(SPI, n, _PUSHR)
+#define SPIn_POPR(n) DO_CONCATENATE(SPI, n, _POPR)
+#define DMAMUX0_CHCFGn(n) DO_CONCATENATE(DMAMUX0, _CHCFG, n)
+#define DMAMUX_SOURCE_SPIn_RX(n) DO_CONCATENATE(DMAMUX_SOURCE_SPI, n, _RX)
+#define DMAMUX_SOURCE_SPIn_TX(n) DO_CONCATENATE(DMAMUX_SOURCE_SPI, n, _TX)
+#define dma_chN_isr(n) DO_CONCATENATE(dma_ch, n, _isr)
+#define IRQ_DMA_CHn(n) DO_CONCATENATE(IRQ_DMA, _CH, n)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  // MOTORS_UTIL_H_