Blackfin arch: rewrite our reboot code in C

rewrite our reboot code in C rather than assembly to be like
other architectures and to allow board maintainers to define
custom behavior

Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

3 files changed, 19 insertions, 26 deletions

diff --git a/arch/blackfin/kernel/Makefile b/arch/blackfin/kernel/Makefile
index f429ebc3a961..ae0a2203c3da 100644
--- a/arch/blackfin/kernel/Makefile
+++ b/arch/blackfin/kernel/Makefile
@@ -7,7 +7,7 @@ extra-y := init_task.o vmlinux.lds
 obj-y := \
         entry.o process.o bfin_ksyms.o ptrace.o setup.o signal.o \
         sys_bfin.o time.o traps.o irqchip.o dma-mapping.o flat.o \
-        fixed_code.o cplbinit.o cacheinit.o
+        fixed_code.o cplbinit.o cacheinit.o reboot.o
 
 obj-$(CONFIG_BF53x)                  += bfin_gpio.o
 obj-$(CONFIG_BF561)                  += bfin_gpio.o
diff --git a/arch/blackfin/kernel/bfin_gpio.c b/arch/blackfin/kernel/bfin_gpio.c
index 0182ce1fc4fb..d9284d7dc9fc 100644
--- a/arch/blackfin/kernel/bfin_gpio.c
+++ b/arch/blackfin/kernel/bfin_gpio.c
@@ -80,6 +80,7 @@
 *  GPIO_47      PH15        PF47
 */
 
+#include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/err.h>
 #include <asm/blackfin.h>
@@ -888,3 +889,20 @@ void gpio_direction_output(unsigned short gpio)
         local_irq_restore(flags);
 }
 EXPORT_SYMBOL(gpio_direction_output);
+
+/* If we are booting from SPI and our board lacks a strong enough pull up,
+ * the core can reset and execute the bootrom faster than the resistor can
+ * pull the signal logically high.  To work around this (common) error in
+ * board design, we explicitly set the pin back to GPIO mode, force /CS
+ * high, and wait for the electrons to do their thing.
+ *
+ * This function only makes sense to be called from reset code, but it
+ * lives here as we need to force all the GPIO states w/out going through
+ * BUG() checks and such.
+ */
+void bfin_gpio_reset_spi0_ssel1(void)
+{
+        port_setup(P_SPI0_SSEL1, GPIO_USAGE);
+        gpio_bankb[gpio_bank(P_SPI0_SSEL1)]->data_set = gpio_bit(P_SPI0_SSEL1);
+        udelay(1);
+}
diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c
index 22e790419868..de7d048bd4ee 100644
--- a/arch/blackfin/kernel/process.c
+++ b/arch/blackfin/kernel/process.c
@@ -134,31 +134,6 @@ void cpu_idle(void)
         }
 }
 
-void machine_restart(char *__unused)
-{
-#if defined(CONFIG_BFIN_ICACHE)
-        bfin_write_IMEM_CONTROL(0x01);
-        SSYNC();
-#endif
-        bfin_reset();
-        /* Dont do anything till the reset occurs */
-        while (1) {
-                SSYNC();
-        }
-}
-
-void machine_halt(void)
-{
-        for (;;)
-                asm volatile ("idle");
-}
-
-void machine_power_off(void)
-{
-        for (;;)
-                asm volatile ("idle");
-}
-
 void show_regs(struct pt_regs *regs)
 {
         printk(KERN_NOTICE "\n");