AVR32: Resource management rewrite

Rewrite the resource management code (i.e. I/O memory, clock gating,
gpio) so it doesn't depend on any global state. This is necessary
because this code is heavily used before relocation to RAM, so we
can't write to any global variables.

As an added bonus, this makes u-boot's memory footprint a bit smaller,
although some functionality has been left out; all clocks are enabled
all the time, and there's no checking for gpio line conflicts.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>

1 files changed, 55 insertions, 9 deletions

diff --git a/cpu/at32ap/cpu.c b/cpu/at32ap/cpu.c
index 37e3ea040b..311466b781 100644
--- a/cpu/at32ap/cpu.c
+++ b/cpu/at32ap/cpu.c
@@ -26,33 +26,79 @@
 #include <asm/sections.h>
 #include <asm/sysreg.h>
 
+#include <asm/arch/clk.h>
 #include <asm/arch/memory-map.h>
-#include <asm/arch/platform.h>
 
 #include "hsmc3.h"
+#include "sm.h"
+
+/* Sanity checks */
+#if (CFG_CLKDIV_CPU > CFG_CLKDIV_HSB)		\
+	|| (CFG_CLKDIV_HSB > CFG_CLKDIV_PBA)	\
+	|| (CFG_CLKDIV_HSB > CFG_CLKDIV_PBB)
+# error Constraint fCPU >= fHSB >= fPB{A,B} violated
+#endif
+#if defined(CONFIG_PLL) && ((CFG_PLL0_MUL < 1) || (CFG_PLL0_DIV < 1))
+# error Invalid PLL multiplier and/or divider
+#endif
 
 DECLARE_GLOBAL_DATA_PTR;
 
+static void pm_init(void)
+{
+	uint32_t cksel;
+
+#ifdef CONFIG_PLL
+	/* Initialize the PLL */
+	sm_writel(PM_PLL0, (SM_BF(PLLCOUNT, CFG_PLL0_SUPPRESS_CYCLES)
+			    | SM_BF(PLLMUL, CFG_PLL0_MUL - 1)
+			    | SM_BF(PLLDIV, CFG_PLL0_DIV - 1)
+			    | SM_BF(PLLOPT, CFG_PLL0_OPT)
+			    | SM_BF(PLLOSC, 0)
+			    | SM_BIT(PLLEN)));
+
+	/* Wait for lock */
+	while (!(sm_readl(PM_ISR) & SM_BIT(LOCK0))) ;
+#endif
+
+	/* Set up clocks for the CPU and all peripheral buses */
+	cksel = 0;
+	if (CFG_CLKDIV_CPU)
+		cksel |= SM_BIT(CPUDIV) | SM_BF(CPUSEL, CFG_CLKDIV_CPU - 1);
+	if (CFG_CLKDIV_HSB)
+		cksel |= SM_BIT(HSBDIV) | SM_BF(HSBSEL, CFG_CLKDIV_HSB - 1);
+	if (CFG_CLKDIV_PBA)
+		cksel |= SM_BIT(PBADIV) | SM_BF(PBASEL, CFG_CLKDIV_PBA - 1);
+	if (CFG_CLKDIV_PBB)
+		cksel |= SM_BIT(PBBDIV) | SM_BF(PBBSEL, CFG_CLKDIV_PBB - 1);
+	sm_writel(PM_CKSEL, cksel);
+
+	gd->cpu_hz = get_cpu_clk_rate();
+
+#ifdef CONFIG_PLL
+	/* Use PLL0 as main clock */
+	sm_writel(PM_MCCTRL, SM_BIT(PLLSEL));
+#endif
+}
+
 int cpu_init(void)
 {
-	const struct device *hebi;
 	extern void _evba(void);
 	char *p;
 
 	gd->cpu_hz = CFG_OSC0_HZ;
 
-	/* fff03400: 00010001 04030402 00050005 10011103 */
-	hebi = get_device(DEVICE_HEBI);
-	hsmc3_writel(hebi, MODE0, 0x00031103);
-	hsmc3_writel(hebi, CYCLE0, 0x000c000d);
-	hsmc3_writel(hebi, PULSE0, 0x0b0a0906);
-	hsmc3_writel(hebi, SETUP0, 0x00010002);
+	/* TODO: Move somewhere else, but needs to be run before we
+	 * increase the clock frequency. */
+	hsmc3_writel(MODE0, 0x00031103);
+	hsmc3_writel(CYCLE0, 0x000c000d);
+	hsmc3_writel(PULSE0, 0x0b0a0906);
+	hsmc3_writel(SETUP0, 0x00010002);
 
 	pm_init();
 
 	sysreg_write(EVBA, (unsigned long)&_evba);
 	asm volatile("csrf	%0" : : "i"(SYSREG_EM_OFFSET));
-	gd->console_uart = get_device(CFG_CONSOLE_UART_DEV);
 
 	/* Lock everything that mess with the flash in the icache */
 	for (p = __flashprog_start; p <= (__flashprog_end + CFG_ICACHE_LINESZ);