Atmel : usb : add EHCI driver for Atmel SoC

Some Atmel SoC support USB EHCI, add the EHCI driver to support it.

To enable the USB EHCI, add the following configuration options into
board relative configuration file and remove USB OHCI options.

    #define CONFIG_USB_EHCI
    #define CONFIG_USB_EHCI_ATMEL
    #define CONFIG_SYS_USB_EHCI_MAX_ROOT_PORTS     2

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>

drivers/usb/host/Makefile

@@ -36,6 +36,7 @@ COBJS-$(CONFIG_USB_SL811HS) += sl811-hcd.o
 # echi
 COBJS-$(CONFIG_USB_EHCI) += ehci-hcd.o
 COBJS-$(CONFIG_USB_EHCI_ARMADA100) += ehci-armada100.o utmi-armada100.o
+COBJS-$(CONFIG_USB_EHCI_ATMEL) += ehci-atmel.o
 ifdef CONFIG_MPC512X
 COBJS-$(CONFIG_USB_EHCI_FSL) += ehci-mpc512x.o
 else

drivers/usb/host/ehci-atmel.c

@@ -0,0 +1,89 @@
+/*
+ * (C) Copyright 2012
+ * Atmel Semiconductor <www.atmel.com>
+ * Written-by: Bo Shen <voice.shen@atmel.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include <common.h>
+#include <watchdog.h>
+#include <usb.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_pmc.h>
+#include <asm/arch/clk.h>
+
+#include "ehci.h"
+#include "ehci-core.h"
+
+/* Enable UTMI PLL time out 500us
+ * 10 times as datasheet specified
+ */
+#define EN_UPLL_TIMEOUT	500UL
+
+int ehci_hcd_init(void)
+{
+	at91_pmc_t *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
+	ulong start_time, tmp_time;
+
+	start_time = get_timer(0);
+	/* Enable UTMI PLL */
+	writel(AT91_PMC_UPLLEN | AT91_PMC_BIASEN, &pmc->uckr);
+	while (readl(&pmc->sr) & AT91_PMC_LOCKU != AT91_PMC_LOCKU) {
+		WATCHDOG_RESET();
+		tmp_time = get_timer(0);
+		if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
+			printf("ERROR: failed to enable UPLL\n");
+			return -1;
+		}
+	}
+
+	/* Enable USB Host clock */
+	writel(1 << ATMEL_ID_UHPHS, &pmc->pcer);
+
+	hccr = (struct ehci_hccr *)ATMEL_BASE_EHCI;
+	hcor = (struct ehci_hcor *)((uint32_t)hccr +
+			HC_LENGTH(ehci_readl(&hccr->cr_capbase)));
+
+	return 0;
+}
+
+int ehci_hcd_stop(void)
+{
+	at91_pmc_t *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
+	ulong start_time, tmp_time;
+
+	/* Disable USB Host Clock */
+	writel(1 << ATMEL_ID_UHPHS, &pmc->pcdr);
+
+	start_time = get_timer(0);
+	/* Disable UTMI PLL */
+	writel(readl(&pmc->uckr) & ~AT91_PMC_UPLLEN, &pmc->uckr);
+	while (readl(&pmc->sr) & AT91_PMC_LOCKU == AT91_PMC_LOCKU) {
+		WATCHDOG_RESET();
+		tmp_time = get_timer(0);
+		if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
+			printf("ERROR: failed to stop UPLL\n");
+			return -1;
+		}
+	}
+
+	return 0;
+}