diff --git a/env/abi_eabi.txt b/env/abi_eabi.txt
new file mode 100644
index 0000000..70dd3c2
--- /dev/null
+++ b/env/abi_eabi.txt
@@ -0,0 +1,52 @@
+            EABI Name  Description                      Saver
+    x0        zero     Hard-wired zero value            -
+    x1        ra       Return address                   Caller
+    x2        sp       Stack pointer                    Callee
+    x3        gp       Global pointer                   -
+    x4        tp       Thread pointer                   -
+    x5        t0       Temporary/link register          Caller
+    x6        s3       Saved register                   Callee
+    x7        s4       Saved register                   Callee
+    x8        s0/fp    Saved register/frame pointer     Callee
+    x9        s1       Saved register                   Callee
+    x10       a0       Argument/return value            Caller
+    x11       a1       Argument/return value            Caller
+    x12       a2       Argument                         Caller
+    x13       a3       Argument                         Caller
+    x14       s2       Saved register                   Callee
+    x15       t1       Temporary                        Caller
+    x16-x31   s5-s20   Saved registers                  Callee
+    
+	reg 	ABI 	Use by convention 					Preserved?
+	x0 	    zero 	hardwired to 0, ignores writes 		n/a
+	x1 	    ra 		return address for jumps 			no
+	x2 	    sp 		stack pointer 						yes
+	x3 	    gp 		global pointer 						n/a
+	x4 	    tp 		thread pointer 						n/a
+	x5 	    t0 		temporary register 0 				no
+	x6 	    t1 		temporary register 1 				no
+	x7 	    t2 		temporary register 2 				no
+	x8 	    s0/fp 	saved register 0 or frame pointer 	yes
+	x9 	    s1 		saved register 1 					yes
+	x10 	a0 		argument/return value 0 			no
+	x11 	a1 		argument/return value 1 			no
+	x12 	a2 		argument 2 							no
+	x13 	a3 		argument 3 							no
+	x14 	a4 		argument 4 							no
+	x15 	a5 		argument 5 							no
+	x16 	a6 		argument 6 							no
+	x17 	a7 		argument 7 							no
+	x18 	s2 		saved register 2 					yes
+	x19 	s3 		saved register 3 					yes
+	x20 	s4 		saved register 4 					yes
+	x21 	s5 		saved register 5 					yes
+	x22 	s6 		saved register 6 					yes
+	x23 	s7 		saved register 7 					yes
+	x24 	s8 		saved register 8 					yes
+	x25 	s9 		saved register 9 					yes
+	x26 	s10 	saved register 10 					yes
+	x27 	s11 	saved register 11 					yes
+	x28 	t3 		temporary register 3 				no
+	x29 	t4 		temporary register 4 				no
+	x30 	t5 		temporary register 5 				no
+	x31 	t6 		temporary register 6 				no
diff --git a/env/ehrenberg/platform.h b/env/ehrenberg/platform.h
index 7da9f8f..632f54d 100644
--- a/env/ehrenberg/platform.h
+++ b/env/ehrenberg/platform.h
@@ -8,104 +8,32 @@
 #define MCAUSE_CAUSE       0x7FFFFFFF
 
 #include "ehrenberg/const.h"
-#include "ehrenberg/devices.h"
 
-/****************************************************************************
- * Platform definitions
- *****************************************************************************/
+#define APB_BUS
 
-// Memory map
-#define MASKROM_BASE_ADDR _AC(0x00001000,UL)
-#define TRAPVEC_TABLE_BASE_ADDR _AC(0x00001010,UL)
-#define OTP_MMAP_ADDR _AC(0x00020000,UL)
-#define CLINT_BASE_ADDR _AC(0x02000000,UL)
-#define PLIC_BASE_ADDR _AC(0x0C000000,UL)
-#define AON_BASE_ADDR _AC(0x10000000,UL)
-#define PRCI_BASE_ADDR _AC(0x10008000,UL)
-#define OTP_BASE_ADDR _AC(0x10010000,UL)
-#define GPIO_BASE_ADDR _AC(0x10012000,UL)
-#define UART0_BASE_ADDR _AC(0x10013000,UL)
-#define SPI0_BASE_ADDR _AC(0x10014000,UL)
-#define PWM0_BASE_ADDR _AC(0x10015000,UL)
-#define UART1_BASE_ADDR _AC(0x10023000,UL)
-#define SPI1_BASE_ADDR _AC(0x10024000,UL)
-#define PWM1_BASE_ADDR _AC(0x10025000,UL)
-#define SPI2_BASE_ADDR _AC(0x10034000,UL)
-#define PWM2_BASE_ADDR _AC(0x10035000,UL)
-#define SPI0_MMAP_ADDR _AC(0x20000000,UL)
-#define MEM_BASE_ADDR _AC(0x80000000,UL)
+#include "devices/gpio.h"
+#include "devices/interrupt.h"
+#include "devices/timer.h"
+#include "devices/uart.h"
+#include "devices/qspi.h"
 
-// IOF masks
-#define IOF0_SPI1_MASK          _AC(0x000007FC,UL)
-#define SPI11_NUM_SS     (4)
-#define IOF_SPI1_SS0          (2u)
-#define IOF_SPI1_SS1          (8u)
-#define IOF_SPI1_SS2          (9u)
-#define IOF_SPI1_SS3          (10u)
-#define IOF_SPI1_MOSI         (3u)
-#define IOF_SPI1_MISO         (4u)
-#define IOF_SPI1_SCK          (5u)
-#define IOF_SPI1_DQ0          (3u)
-#define IOF_SPI1_DQ1          (4u)
-#define IOF_SPI1_DQ2          (6u)
-#define IOF_SPI1_DQ3          (7u)
+#define PERIPH(TYPE, ADDR) ((volatile TYPE*) (ADDR))
 
-#define IOF0_SPI2_MASK          _AC(0xFC000000,UL)
-#define SPI2_NUM_SS       (1)
-#define IOF_SPI2_SS0          (26u)
-#define IOF_SPI2_MOSI         (27u)
-#define IOF_SPI2_MISO         (28u)
-#define IOF_SPI2_SCK          (29u)
-#define IOF_SPI2_DQ0          (27u)
-#define IOF_SPI2_DQ1          (28u)
-#define IOF_SPI2_DQ2          (30u)
-#define IOF_SPI2_DQ3          (31u)
+#define APB_BASE 0xF0000000
+#define TIMER_BASE                 (APB_BASE+0x30000)
 
-//#define IOF0_I2C_MASK          _AC(0x00003000,UL)
+#define gpio_a    PERIPH(gpio_t,   APB_BASE+0x00000)
+//#define gpio_b     PERIPH(gpio_t, APB_BASE+0x10000)
+#define uart      PERIPH(uart_t,   APB_BASE+0x10000)
+#define prescaler PERIPH(uart_t,   TIMER_BASE+0x0)
+#define timer_a   PERIPH(uart_t,   TIMER_BASE+0x10)
+#define timer_b   PERIPH(uart_t,   TIMER_BASE+0x20)
+#define mtimer    PERIPH(mtimer_t, APB_BASE+0x30000)
+#define irq       PERIPH(irq_t,    APB_BASE+0x40000)
+#define qspi      PERIPH(qspi_t,   APB_BASE+0x50000)
+//volatile qspi_t*   const qspi       = (qspi_t*)(APB_BASE+0x50000);
 
-#define IOF0_UART0_MASK         _AC(0x00030000, UL)
-#define IOF_UART0_RX   (16u)
-#define IOF_UART0_TX   (17u)
-
-#define IOF0_UART1_MASK         _AC(0x03000000, UL)
-#define IOF_UART1_RX (24u)
-#define IOF_UART1_TX (25u)
-
-#define IOF1_PWM0_MASK          _AC(0x0000000F, UL)
-#define IOF1_PWM1_MASK          _AC(0x00780000, UL)
-#define IOF1_PWM2_MASK          _AC(0x00003C00, UL)
-
-// Interrupt numbers
-#define INT_RESERVED 0
-#define INT_WDOGCMP 1
-#define INT_RTCCMP 2
-#define INT_UART0_BASE 3
-#define INT_UART1_BASE 4
-#define INT_SPI0_BASE 5
-#define INT_SPI1_BASE 6
-#define INT_SPI2_BASE 7
-#define INT_GPIO_BASE 8
-#define INT_PWM0_BASE 40
-#define INT_PWM1_BASE 44
-#define INT_PWM2_BASE 48
-
-// Helper functions
-#define _REG32(p, i) (*(volatile uint32_t *) ((p) + (i)))
-#define _REG32P(p, i) ((volatile uint32_t *) ((p) + (i)))
-#define AON_REG(offset) _REG32(AON_BASE_ADDR, offset)
-#define CLINT_REG(offset) _REG32(CLINT_BASE_ADDR, offset)
-#define GPIO_REG(offset) _REG32(GPIO_BASE_ADDR, offset)
-#define OTP_REG(offset)  _REG32(OTP_BASE_ADDR, offset)
-#define PLIC_REG(offset) _REG32(PLIC_BASE_ADDR, offset)
-#define PRCI_REG(offset) _REG32(PRCI_BASE_ADDR, offset)
-#define PWM0_REG(offset) _REG32(PWM0_BASE_ADDR, offset)
-#define PWM1_REG(offset) _REG32(PWM1_BASE_ADDR, offset)
-#define PWM2_REG(offset) _REG32(PWM2_BASE_ADDR, offset)
-#define SPI0_REG(offset) _REG32(SPI0_BASE_ADDR, offset)
-#define SPI1_REG(offset) _REG32(SPI1_BASE_ADDR, offset)
-#define SPI2_REG(offset) _REG32(SPI2_BASE_ADDR, offset)
-#define UART0_REG(offset) _REG32(UART0_BASE_ADDR, offset)
-#define UART1_REG(offset) _REG32(UART1_BASE_ADDR, offset)
+#define XIP_START_LOC 0xE0040000
 
 // Misc
 
diff --git a/env/entry.S b/env/entry.S
index 9d61210..982c664 100644
--- a/env/entry.S
+++ b/env/entry.S
@@ -10,85 +10,67 @@
   .align 2
   .global trap_entry
 trap_entry:
-  addi sp, sp, -32*REGBYTES
-
-  STORE x1, 1*REGBYTES(sp)
-  STORE x2, 2*REGBYTES(sp)
-  STORE x3, 3*REGBYTES(sp)
-  STORE x4, 4*REGBYTES(sp)
-  STORE x5, 5*REGBYTES(sp)
-  STORE x6, 6*REGBYTES(sp)
-  STORE x7, 7*REGBYTES(sp)
-  STORE x8, 8*REGBYTES(sp)
-  STORE x9, 9*REGBYTES(sp)
-  STORE x10, 10*REGBYTES(sp)
-  STORE x11, 11*REGBYTES(sp)
-  STORE x12, 12*REGBYTES(sp)
-  STORE x13, 13*REGBYTES(sp)
-  STORE x14, 14*REGBYTES(sp)
-  STORE x15, 15*REGBYTES(sp)
 #ifndef __riscv_abi_rve
-  STORE x16, 16*REGBYTES(sp)
-  STORE x17, 17*REGBYTES(sp)
-  STORE x18, 18*REGBYTES(sp)
-  STORE x19, 19*REGBYTES(sp)
-  STORE x20, 20*REGBYTES(sp)
-  STORE x21, 21*REGBYTES(sp)
-  STORE x22, 22*REGBYTES(sp)
-  STORE x23, 23*REGBYTES(sp)
-  STORE x24, 24*REGBYTES(sp)
-  STORE x25, 25*REGBYTES(sp)
-  STORE x26, 26*REGBYTES(sp)
-  STORE x27, 27*REGBYTES(sp)
-  STORE x28, 28*REGBYTES(sp)
-  STORE x29, 29*REGBYTES(sp)
-  STORE x30, 30*REGBYTES(sp)
-  STORE x31, 31*REGBYTES(sp)
+  addi sp, sp, -8*REGBYTES
+  STORE x1, 1*REGBYTES(sp) // ra
+  STORE x5, 2*REGBYTES(sp) // t0
+  STORE x10, 3*REGBYTES(sp) // a0
+  STORE x11, 4*REGBYTES(sp) // a1
+  STORE x12, 5*REGBYTES(sp) // a2
+  STORE x13, 6*REGBYTES(sp) // a3
+  STORE x15, 7*REGBYTES(sp) // t1
+#else
+  addi sp, sp, -16*REGBYTES
+  STORE x1, 1*REGBYTES(sp) // ra
+  STORE x5, 2*REGBYTES(sp) // t0
+  STORE x6, 3*REGBYTES(sp) // t1
+  STORE x7, 4*REGBYTES(sp) // t2
+  STORE x10, 5*REGBYTES(sp) // a0
+  STORE x11, 6*REGBYTES(sp) // a1
+  STORE x12, 7*REGBYTES(sp) // a2
+  STORE x13, 8*REGBYTES(sp) // a3
+  STORE x14, 9*REGBYTES(sp) // a4
+  STORE x15, 10*REGBYTES(sp) // a5
+  STORE x16, 11*REGBYTES(sp) // a6
+  STORE x17, 12*REGBYTES(sp) // a7
+  STORE x28, 13*REGBYTES(sp) // t3
+  STORE x29, 14*REGBYTES(sp) // t4
+  STORE x30, 15*REGBYTES(sp) // t5
+  STORE x31, 16*REGBYTES(sp) // t6
 #endif
   csrr a0, mcause
   csrr a1, mepc
   mv a2, sp
   call handle_trap
   csrw mepc, a0
-
-  # Remain in M-mode after mret
-  li t0, MSTATUS_MPP
-  csrs mstatus, t0
-
-  LOAD x1, 1*REGBYTES(sp)
-  LOAD x2, 2*REGBYTES(sp)
-  LOAD x3, 3*REGBYTES(sp)
-  LOAD x4, 4*REGBYTES(sp)
-  LOAD x5, 5*REGBYTES(sp)
-  LOAD x6, 6*REGBYTES(sp)
-  LOAD x7, 7*REGBYTES(sp)
-  LOAD x8, 8*REGBYTES(sp)
-  LOAD x9, 9*REGBYTES(sp)
-  LOAD x10, 10*REGBYTES(sp)
-  LOAD x11, 11*REGBYTES(sp)
-  LOAD x12, 12*REGBYTES(sp)
-  LOAD x13, 13*REGBYTES(sp)
-  LOAD x14, 14*REGBYTES(sp)
-  LOAD x15, 15*REGBYTES(sp)
 #ifndef __riscv_abi_rve
-  LOAD x16, 16*REGBYTES(sp)
-  LOAD x17, 17*REGBYTES(sp)
-  LOAD x18, 18*REGBYTES(sp)
-  LOAD x19, 19*REGBYTES(sp)
-  LOAD x20, 20*REGBYTES(sp)
-  LOAD x21, 21*REGBYTES(sp)
-  LOAD x22, 22*REGBYTES(sp)
-  LOAD x23, 23*REGBYTES(sp)
-  LOAD x24, 24*REGBYTES(sp)
-  LOAD x25, 25*REGBYTES(sp)
-  LOAD x26, 26*REGBYTES(sp)
-  LOAD x27, 27*REGBYTES(sp)
-  LOAD x28, 28*REGBYTES(sp)
-  LOAD x29, 29*REGBYTES(sp)
-  LOAD x30, 30*REGBYTES(sp)
-  LOAD x31, 31*REGBYTES(sp)
+  addi sp, sp, -8*REGBYTES
+  LOAD x1, 1*REGBYTES(sp) // ra
+  LOAD x5, 2*REGBYTES(sp) // t0
+  LOAD x10, 3*REGBYTES(sp) // a0
+  LOAD x11, 4*REGBYTES(sp) // a1
+  LOAD x12, 5*REGBYTES(sp) // a2
+  LOAD x13, 6*REGBYTES(sp) // a3
+  LOAD x15, 7*REGBYTES(sp) // t1
+#else
+  addi sp, sp, -16*REGBYTES
+  LOAD x1, 1*REGBYTES(sp) // ra
+  LOAD x5, 2*REGBYTES(sp) // t0
+  LOAD x6, 3*REGBYTES(sp) // t1
+  LOAD x7, 4*REGBYTES(sp) // t2
+  LOAD x10, 5*REGBYTES(sp) // a0
+  LOAD x11, 6*REGBYTES(sp) // a1
+  LOAD x12, 7*REGBYTES(sp) // a2
+  LOAD x13, 8*REGBYTES(sp) // a3
+  LOAD x14, 9*REGBYTES(sp) // a4
+  LOAD x15, 10*REGBYTES(sp) // a5
+  LOAD x16, 11*REGBYTES(sp) // a6
+  LOAD x17, 12*REGBYTES(sp) // a7
+  LOAD x28, 13*REGBYTES(sp) // t3
+  LOAD x29, 14*REGBYTES(sp) // t4
+  LOAD x30, 15*REGBYTES(sp) // t5
+  LOAD x31, 16*REGBYTES(sp) // t6
 #endif
-  addi sp, sp, 32*REGBYTES
   mret
 
 .weak handle_trap
diff --git a/env/hifive1/platform.h b/env/hifive1/platform.h
index 806fcfc..e3631b0 100644
--- a/env/hifive1/platform.h
+++ b/env/hifive1/platform.h
@@ -7,7 +7,7 @@
 #define MCAUSE_INT         0x80000000
 #define MCAUSE_CAUSE       0x7FFFFFFF
 
-#include "sifive/const.h"
+#include "bits.h"
 #include "sifive/devices/aon.h"
 #include "sifive/devices/clint.h"
 #include "sifive/devices/gpio.h"
diff --git a/env/rtl/platform.h b/env/rtl/platform.h
index 59e6fd5..93934f4 100644
--- a/env/rtl/platform.h
+++ b/env/rtl/platform.h
@@ -7,7 +7,18 @@
 #define MCAUSE_INT         0x80000000
 #define MCAUSE_CAUSE       0x7FFFFFFF
 
-#include "rtl/const.h"
+#define UART0_BASE_ADDR 0xffff0000ULL
+
+#define UART_REG_TXFIFO         0x00
+#define UART_REG_RXFIFO         0x04
+#define UART_REG_TXCTRL         0x08
+#define UART_REG_RXCTRL         0x0c
+#define UART_REG_IE             0x10
+#define UART_REG_IP             0x14
+#define UART_REG_DIV            0x18
+#define UART_TXEN               0x1
+
+#define UART0_REG(ADDR) *((volatile uint32_t*) (UART0_BASE_ADDR + ADDR))
 /****************************************************************************
  * Platform definitions
  *****************************************************************************/
diff --git a/env/start.S b/env/start.S
index 0c26749..46ab3de 100644
--- a/env/start.S
+++ b/env/start.S
@@ -5,10 +5,10 @@
 	.type _start,@function
 
 _start:
-    la gp, trap_entry
-    csrw mtvec, gp
 .option push
 .option norelax
+    la gp, trap_entry
+    csrw mtvec, gp
     la gp, __global_pointer$
 .option pop
 	la sp, _sp
diff --git a/include/tgc-vp/bits.h b/include/bits.h
similarity index 77%
rename from include/tgc-vp/bits.h
rename to include/bits.h
index e550f80..fd40990 100644
--- a/include/tgc-vp/bits.h
+++ b/include/bits.h
@@ -32,4 +32,15 @@
 #endif
 #define REGBYTES (1 << LOG_REGBYTES)
 
+#ifdef __ASSEMBLER__
+#define _AC(X,Y)        X
+#define _AT(T,X)        X
+#else
+#define _AC(X,Y)        (X##Y)
+#define _AT(T,X)        ((T)(X))
+#endif /* !__ASSEMBLER__*/
+
+#define _BITUL(x)       (_AC(1,UL) << (x))
+#define _BITULL(x)      (_AC(1,ULL) << (x))
+
 #endif
diff --git a/include/ehrenberg/const.h b/include/ehrenberg/const.h
deleted file mode 100644
index 8dcffbb..0000000
--- a/include/ehrenberg/const.h
+++ /dev/null
@@ -1,18 +0,0 @@
-// See LICENSE for license details.
-/* Derived from <linux/const.h> */
-
-#ifndef _SIFIVE_CONST_H
-#define _SIFIVE_CONST_H
-
-#ifdef __ASSEMBLER__
-#define _AC(X,Y)        X
-#define _AT(T,X)        X
-#else
-#define _AC(X,Y)        (X##Y)
-#define _AT(T,X)        ((T)(X))
-#endif /* !__ASSEMBLER__*/
-
-#define _BITUL(x)       (_AC(1,UL) << (x))
-#define _BITULL(x)      (_AC(1,ULL) << (x))
-
-#endif /* _SIFIVE_CONST_H */
diff --git a/include/ehrenberg/devices.h b/include/ehrenberg/devices.h
deleted file mode 100644
index c18f422..0000000
--- a/include/ehrenberg/devices.h
+++ /dev/null
@@ -1,37 +0,0 @@
-/*
- * devices.c
- *
- *  Created on: Aug 15, 2020
- *      Author: eyck
- */
-
-#ifndef _BSP_EHRENBERG_DEVICES_C_
-#define _BSP_EHRENBERG_DEVICES_C_
-
-#define APB_BUS
-
-#include "devices/gpio.h"
-#include "devices/interrupt.h"
-#include "devices/timer.h"
-#include "devices/uart.h"
-#include "devices/qspi.h"
-
-#define PERIPH(TYPE, ADDR) ((volatile TYPE*) (ADDR))
-
-#define APB_BASE 0xF0000000
-#define TIMER_BASE                 (APB_BASE+0x30000)
-
-#define gpio_a    PERIPH(gpio_t,   APB_BASE+0x00000)
-//#define gpio_b     PERIPH(gpio_t, APB_BASE+0x10000)
-#define uart      PERIPH(uart_t,   APB_BASE+0x10000)
-#define prescaler PERIPH(uart_t,   TIMER_BASE+0x0)
-#define timer_a   PERIPH(uart_t,   TIMER_BASE+0x10)
-#define timer_b   PERIPH(uart_t,   TIMER_BASE+0x20)
-#define mtimer    PERIPH(mtimer_t, APB_BASE+0x30000)
-#define irq       PERIPH(irq_t,    APB_BASE+0x40000)
-#define qspi      PERIPH(qspi_t,   APB_BASE+0x50000)
-//volatile qspi_t*   const qspi       = (qspi_t*)(APB_BASE+0x50000);
-
-#define XIP_START_LOC 0xE0040000
-
-#endif /* _BSP_EHRENBERG_DEVICES_C_ */
diff --git a/include/rtl/bits.h b/include/rtl/bits.h
deleted file mode 100644
index e550f80..0000000
--- a/include/rtl/bits.h
+++ /dev/null
@@ -1,35 +0,0 @@
-#ifndef _RISCV_BITS_H
-#define _RISCV_BITS_H
-
-#define likely(x) __builtin_expect((x), 1)
-#define unlikely(x) __builtin_expect((x), 0)
-
-#define ROUNDUP(a, b) ((((a)-1)/(b)+1)*(b))
-#define ROUNDDOWN(a, b) ((a)/(b)*(b))
-
-#define MAX(a, b) ((a) > (b) ? (a) : (b))
-#define MIN(a, b) ((a) < (b) ? (a) : (b))
-#define CLAMP(a, lo, hi) MIN(MAX(a, lo), hi)
-
-#define EXTRACT_FIELD(val, which) (((val) & (which)) / ((which) & ~((which)-1)))
-#define INSERT_FIELD(val, which, fieldval) (((val) & ~(which)) | ((fieldval) * ((which) & ~((which)-1))))
-
-#define STR(x) XSTR(x)
-#define XSTR(x) #x
-
-#ifdef __riscv64
-# define SLL32    sllw
-# define STORE    sd
-# define LOAD     ld
-# define LWU      lwu
-# define LOG_REGBYTES 3
-#else
-# define SLL32    sll
-# define STORE    sw
-# define LOAD     lw
-# define LWU      lw
-# define LOG_REGBYTES 2
-#endif
-#define REGBYTES (1 << LOG_REGBYTES)
-
-#endif
diff --git a/include/rtl/const.h b/include/rtl/const.h
deleted file mode 100644
index 7e62f93..0000000
--- a/include/rtl/const.h
+++ /dev/null
@@ -1,27 +0,0 @@
-#ifndef _RTL_CONST_H
-#define _RTL_CONST_H
-
-#ifdef __ASSEMBLER__
-#define _AC(X,Y)        X
-#define _AT(T,X)        X
-#else
-#define _AC(X,Y)        (X##Y)
-#define _AT(T,X)        ((T)(X))
-#endif /* !__ASSEMBLER__*/
-
-#define _BITUL(x)       (_AC(1,UL) << (x))
-#define _BITULL(x)      (_AC(1,ULL) << (x))
-
-#define UART0_BASE_ADDR 0xffff0000ULL
-
-#define UART_REG_TXFIFO         0x00
-#define UART_REG_RXFIFO         0x04
-#define UART_REG_TXCTRL         0x08
-#define UART_REG_RXCTRL         0x0c
-#define UART_REG_IE             0x10
-#define UART_REG_IP             0x14
-#define UART_REG_DIV            0x18
-#define UART_TXEN               0x1
-
-#define UART0_REG(ADDR) *((volatile uint32_t*) (UART0_BASE_ADDR + ADDR))
-#endif /* _RTL_CONST_H */
diff --git a/include/rtl/sections.h b/include/sections.h
similarity index 100%
rename from include/rtl/sections.h
rename to include/sections.h
diff --git a/include/sifive/bits.h b/include/sifive/bits.h
deleted file mode 100644
index bfe656f..0000000
--- a/include/sifive/bits.h
+++ /dev/null
@@ -1,36 +0,0 @@
-// See LICENSE for license details.
-#ifndef _RISCV_BITS_H
-#define _RISCV_BITS_H
-
-#define likely(x) __builtin_expect((x), 1)
-#define unlikely(x) __builtin_expect((x), 0)
-
-#define ROUNDUP(a, b) ((((a)-1)/(b)+1)*(b))
-#define ROUNDDOWN(a, b) ((a)/(b)*(b))
-
-#define MAX(a, b) ((a) > (b) ? (a) : (b))
-#define MIN(a, b) ((a) < (b) ? (a) : (b))
-#define CLAMP(a, lo, hi) MIN(MAX(a, lo), hi)
-
-#define EXTRACT_FIELD(val, which) (((val) & (which)) / ((which) & ~((which)-1)))
-#define INSERT_FIELD(val, which, fieldval) (((val) & ~(which)) | ((fieldval) * ((which) & ~((which)-1))))
-
-#define STR(x) XSTR(x)
-#define XSTR(x) #x
-
-#if __riscv_xlen == 64
-# define SLL32    sllw
-# define STORE    sd
-# define LOAD     ld
-# define LWU      lwu
-# define LOG_REGBYTES 3
-#else
-# define SLL32    sll
-# define STORE    sw
-# define LOAD     lw
-# define LWU      lw
-# define LOG_REGBYTES 2
-#endif
-#define REGBYTES (1 << LOG_REGBYTES)
-
-#endif
diff --git a/include/sifive/const.h b/include/sifive/const.h
deleted file mode 100644
index 8dcffbb..0000000
--- a/include/sifive/const.h
+++ /dev/null
@@ -1,18 +0,0 @@
-// See LICENSE for license details.
-/* Derived from <linux/const.h> */
-
-#ifndef _SIFIVE_CONST_H
-#define _SIFIVE_CONST_H
-
-#ifdef __ASSEMBLER__
-#define _AC(X,Y)        X
-#define _AT(T,X)        X
-#else
-#define _AC(X,Y)        (X##Y)
-#define _AT(T,X)        ((T)(X))
-#endif /* !__ASSEMBLER__*/
-
-#define _BITUL(x)       (_AC(1,UL) << (x))
-#define _BITULL(x)      (_AC(1,ULL) << (x))
-
-#endif /* _SIFIVE_CONST_H */
diff --git a/include/sifive/sections.h b/include/sifive/sections.h
deleted file mode 100644
index 6e1f051..0000000
--- a/include/sifive/sections.h
+++ /dev/null
@@ -1,17 +0,0 @@
-// See LICENSE for license details.
-#ifndef _SECTIONS_H
-#define _SECTIONS_H
-
-extern unsigned char _rom[];
-extern unsigned char _rom_end[];
-
-extern unsigned char _ram[];
-extern unsigned char _ram_end[];
-
-extern unsigned char _ftext[];
-extern unsigned char _etext[];
-extern unsigned char _fbss[];
-extern unsigned char _ebss[];
-extern unsigned char _end[];
-
-#endif /* _SECTIONS_H */
diff --git a/include/tgc-vp/const.h b/include/tgc-vp/const.h
deleted file mode 100644
index 3e0a681..0000000
--- a/include/tgc-vp/const.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/* Derived from <linux/const.h> */
-
-#ifndef _SIFIVE_CONST_H
-#define _SIFIVE_CONST_H
-
-#ifdef __ASSEMBLER__
-#define _AC(X,Y)        X
-#define _AT(T,X)        X
-#else
-#define _AC(X,Y)        (X##Y)
-#define _AT(T,X)        ((T)(X))
-#endif /* !__ASSEMBLER__*/
-
-#define _BITUL(x)       (_AC(1,UL) << (x))
-#define _BITULL(x)      (_AC(1,ULL) << (x))
-
-#endif /* _SIFIVE_CONST_H */
diff --git a/include/tgc-vp/sections.h b/include/tgc-vp/sections.h
deleted file mode 100644
index 848c237..0000000
--- a/include/tgc-vp/sections.h
+++ /dev/null
@@ -1,16 +0,0 @@
-#ifndef _SECTIONS_H
-#define _SECTIONS_H
-
-extern unsigned char _rom[];
-extern unsigned char _rom_end[];
-
-extern unsigned char _ram[];
-extern unsigned char _ram_end[];
-
-extern unsigned char _ftext[];
-extern unsigned char _etext[];
-extern unsigned char _fbss[];
-extern unsigned char _ebss[];
-extern unsigned char _end[];
-
-#endif /* _SECTIONS_H */