stm32: add support for stm32f7 & stm32f746 discovery board

This patch adds support for stm32f7 family & stm32f746 board.

Signed-off-by: Vikas Manocha <vikas.manocha@st.com>

arch/arm/mach-stm32/stm32f7/Kconfig

@@ -0,0 +1,8 @@
+if STM32F7
+
+config TARGET_STM32F746_DISCO
+	bool "STM32F746 Discovery board"
+
+source "board/st/stm32f746-disco/Kconfig"
+
+endif

arch/arm/mach-stm32/stm32f7/Makefile

@@ -0,0 +1,8 @@
+#
+# (C) Copyright 2016
+# Vikas Manocha, <vikas.manocha@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += timer.o clock.o

arch/arm/mach-stm32/stm32f7/clock.c

@@ -0,0 +1,56 @@
+/*
+ * (C) Copyright 2016
+ * Vikas Manocha, <vikas.manocha@st.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/rcc.h>
+#include <asm/arch/stm32.h>
+#include <asm/arch/stm32_periph.h>
+
+void clock_setup(int peripheral)
+{
+	switch (peripheral) {
+	case USART1_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_APB2ENR, RCC_ENR_USART1EN);
+		break;
+	case GPIO_A_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_A_EN);
+		break;
+	case GPIO_B_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_B_EN);
+		break;
+	case GPIO_C_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_C_EN);
+		break;
+	case GPIO_D_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_D_EN);
+		break;
+	case GPIO_E_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_E_EN);
+		break;
+	case GPIO_F_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_F_EN);
+		break;
+	case GPIO_G_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_G_EN);
+		break;
+	case GPIO_H_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_H_EN);
+		break;
+	case GPIO_I_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_I_EN);
+		break;
+	case GPIO_J_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_J_EN);
+		break;
+	case GPIO_K_CLOCK_CFG:
+		setbits_le32(RCC_BASE + RCC_AHB1ENR, RCC_ENR_GPIO_K_EN);
+		break;
+	default:
+		break;
+	}
+}

arch/arm/mach-stm32/stm32f7/timer.c

@@ -0,0 +1,112 @@
+/*
+ * (C) Copyright 2016
+ * Vikas Manocha, ST Micoelectronics, vikas.manocha@st.com.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/stm32.h>
+#include <asm/arch/gpt.h>
+#include <asm/arch/rcc.h>
+
+#define READ_TIMER()	(readl(&gpt1_regs_ptr->cnt) & GPT_FREE_RUNNING)
+#define GPT_RESOLUTION	(CONFIG_SYS_HZ_CLOCK/CONFIG_STM32_HZ)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define timestamp gd->arch.tbl
+#define lastdec gd->arch.lastinc
+
+int timer_init(void)
+{
+	/* Timer2 clock configuration */
+	setbits_le32(RCC_BASE + RCC_APB1ENR, RCC_APB1ENR_TIM2EN);
+	/* Stop the timer */
+	writel(readl(&gpt1_regs_ptr->cr1) & ~GPT_CR1_CEN, &gpt1_regs_ptr->cr1);
+
+	writel((CONFIG_SYS_CLK_FREQ/CONFIG_SYS_HZ_CLOCK) - 1,
+						&gpt1_regs_ptr->psc);
+
+	/* Configure timer for auto-reload */
+	writel(readl(&gpt1_regs_ptr->cr1) | GPT_MODE_AUTO_RELOAD,
+						&gpt1_regs_ptr->cr1);
+
+	/* load value for free running */
+	writel(GPT_FREE_RUNNING, &gpt1_regs_ptr->arr);
+
+	/* start timer */
+	writel(readl(&gpt1_regs_ptr->cr1) | GPT_CR1_CEN, &gpt1_regs_ptr->cr1);
+
+	writel(readl(&gpt1_regs_ptr->egr) | TIM_EGR_UG, &gpt1_regs_ptr->egr);
+
+	/* Reset the timer */
+	lastdec = READ_TIMER();
+	timestamp = 0;
+
+	return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+ulong get_timer(ulong base)
+{
+	return (get_timer_masked() / GPT_RESOLUTION) - base;
+}
+
+void __udelay(unsigned long usec)
+{
+	ulong tmo;
+	ulong start = get_timer_masked();
+	ulong tenudelcnt = CONFIG_SYS_HZ_CLOCK / (1000 * 100);
+	ulong rndoff;
+
+	rndoff = (usec % 10) ? 1 : 0;
+
+	/* tenudelcnt timer tick gives 10 microsecconds delay */
+	tmo = ((usec / 10) + rndoff) * tenudelcnt;
+
+	while ((ulong) (get_timer_masked() - start) < tmo)
+		;
+}
+
+ulong get_timer_masked(void)
+{
+	ulong now = READ_TIMER();
+
+	if (now >= lastdec) {
+		/* normal mode */
+		timestamp += now - lastdec;
+	} else {
+		/* we have an overflow ... */
+		timestamp += now + GPT_FREE_RUNNING - lastdec;
+	}
+	lastdec = now;
+
+	return timestamp;
+}
+
+void udelay_masked(unsigned long usec)
+{
+	return udelay(usec);
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+	return get_timer(0);
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+	return CONFIG_STM32_HZ;
+}