From d9e1680800583525d3a968ba31d0ca86a6262b69 Mon Sep 17 00:00:00 2001
From: Maximilian Rehkopf <ikari@elektra.micecat.ath.cx>
Date: Sun, 1 Jul 2012 03:15:27 +0200
Subject: [PATCH] Firmware: remove SPI speed switching

---
 src/config.h   |  6 +-----
 src/fpga_spi.c |  2 +-
 src/fpga_spi.h |  3 ---
 src/spi.c      | 34 ++--------------------------------
 src/spi.h      |  5 +----
 5 files changed, 5 insertions(+), 45 deletions(-)

diff --git a/src/config.h b/src/config.h
index 91ae55d..6e64271 100644
--- a/src/config.h
+++ b/src/config.h
@@ -42,11 +42,7 @@
 #define CONFIG_UART_BAUDRATE      921600
 #define CONFIG_UART_DEADLOCKABLE
 
-#define SSP_CLK_DIVISOR_FAST 2
-#define SSP_CLK_DIVISOR_SLOW 250
-
-#define SSP_CLK_DIVISOR_FPGA_FAST 6
-#define SSP_CLK_DIVISOR_FPGA_SLOW 20
+#define SSP_CLK_DIVISOR           2
 
 #define SNES_RESET_REG            LPC_GPIO1
 #define SNES_RESET_BIT            26
diff --git a/src/fpga_spi.c b/src/fpga_spi.c
index 8f44916..b407d3c 100644
--- a/src/fpga_spi.c
+++ b/src/fpga_spi.c
@@ -143,7 +143,7 @@
 #include "sdnative.h"
 
 void fpga_spi_init(void) {
-  spi_init(SPI_SPEED_FAST);
+  spi_init();
   BITBAND(FPGA_MCU_RDY_REG->FIODIR, FPGA_MCU_RDY_BIT) = 0;
 }
 
diff --git a/src/fpga_spi.h b/src/fpga_spi.h
index b13c382..f4e8f28 100644
--- a/src/fpga_spi.h
+++ b/src/fpga_spi.h
@@ -47,9 +47,6 @@
 #define FPGA_TX_BLOCK(x,y) spi_tx_block(x,y)
 #define FPGA_RX_BLOCK(x,y) spi_rx_block(x,y)
 
-#define FPGA_SPI_FAST()    spi_set_speed(SPI_SPEED_FPGA_FAST)
-#define FPGA_SPI_SLOW()    spi_set_speed(SPI_SPEED_FPGA_SLOW)
-
 #define FEAT_213F          (1 << 4)
 #define FEAT_MSU1          (1 << 3)
 #define FEAT_SRTC          (1 << 2)
diff --git a/src/spi.c b/src/spi.c
index 2893a7a..f3c6a6f 100644
--- a/src/spi.c
+++ b/src/spi.c
@@ -36,21 +36,13 @@ void spi_preinit() {
   BITBAND(LPC_SC->SSP_PCLKREG, SSP_PCLKBIT) = 1;
 }
 
-void spi_init(spi_speed_t speed) {
+void spi_init() {
 
   /* configure data format - 8 bits, SPI, CPOL=0, CPHA=0, 1 clock per bit */
   SSP_REGS->CR0 = (8-1);
 
   /* set clock prescaler */
-  if (speed == SPI_SPEED_FAST) {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_FAST;
-  } else if (speed == SPI_SPEED_SLOW) {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_SLOW;
-  } else if (speed == SPI_SPEED_FPGA_FAST) {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_FPGA_FAST;
-  } else {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_FPGA_SLOW;
-  }
+  SSP_REGS->CPSR = SSP_CLK_DIVISOR;
 
   /* Enable SSP */
   SSP_REGS->CR1 = BV(1);
@@ -189,25 +181,3 @@ void spi_rx_block(void *ptr, unsigned int length) {
     SSP_REGS->DMACR = 0;
   }
 }
-
-void spi_set_speed(spi_speed_t speed) {
-  /* Wait until TX fifo is empty */
-  while (!BITBAND(SSP_REGS->SR, 0)) ;
-
-  /* Disable SSP (FIXME: Is this required?) */
-  SSP_REGS->CR1 = 0;
-
-  /* Change clock divisor */
-  if (speed == SPI_SPEED_FAST) {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_FAST;
-  } else if (speed == SPI_SPEED_SLOW) {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_SLOW;
-  } else if (speed == SPI_SPEED_FPGA_FAST) {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_FPGA_FAST;
-  } else {
-    SSP_REGS->CPSR = SSP_CLK_DIVISOR_FPGA_SLOW;
-  }
-
-  /* Enable SSP */
-  SSP_REGS->CR1 = BV(1);
-}
diff --git a/src/spi.h b/src/spi.h
index 8bb7a8c..b90c092 100644
--- a/src/spi.h
+++ b/src/spi.h
@@ -42,7 +42,7 @@ typedef enum { SPI_SPEED_FAST, SPI_SPEED_SLOW, SPI_SPEED_FPGA_FAST, SPI_SPEED_FP
 void spi_preinit(void);
 
 /* Initialize SPI interface */
-void spi_init(spi_speed_t speed);
+void spi_init(void);
 
 /* Transmit a single byte */
 void spi_tx_byte(uint8_t data);
@@ -59,9 +59,6 @@ uint8_t spi_rx_byte(void);
 /* Receive a data block */
 void spi_rx_block(void *data, unsigned int length);
 
-/* Switch speed of SPI interface */
-void spi_set_speed(spi_speed_t speed);
-
 /* wait for SPI TX FIFO to become empty */
 void spi_tx_sync(void);