xref: /openbmc/u-boot/drivers/usb/host/ehci-atmel.c (revision 901d0ea1)
1 /*
2  * (C) Copyright 2012
3  * Atmel Semiconductor <www.atmel.com>
4  * Written-by: Bo Shen <voice.shen@atmel.com>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <watchdog.h>
11 #include <usb.h>
12 #include <asm/io.h>
13 #include <asm/arch/hardware.h>
14 #include <asm/arch/at91_pmc.h>
15 #include <asm/arch/clk.h>
16 
17 #include "ehci.h"
18 
19 /* Enable UTMI PLL time out 500us
20  * 10 times as datasheet specified
21  */
22 #define EN_UPLL_TIMEOUT	500UL
23 
24 int ehci_hcd_init(int index, enum usb_init_type init,
25 		struct ehci_hccr **hccr, struct ehci_hcor **hcor)
26 {
27 	at91_pmc_t *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
28 	ulong start_time, tmp_time;
29 
30 	start_time = get_timer(0);
31 	/* Enable UTMI PLL */
32 	writel(AT91_PMC_UPLLEN | AT91_PMC_BIASEN, &pmc->uckr);
33 	while ((readl(&pmc->sr) & AT91_PMC_LOCKU) != AT91_PMC_LOCKU) {
34 		WATCHDOG_RESET();
35 		tmp_time = get_timer(0);
36 		if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
37 			printf("ERROR: failed to enable UPLL\n");
38 			return -1;
39 		}
40 	}
41 
42 	/* Enable USB Host clock */
43 	writel(1 << ATMEL_ID_UHPHS, &pmc->pcer);
44 
45 	*hccr = (struct ehci_hccr *)ATMEL_BASE_EHCI;
46 	*hcor = (struct ehci_hcor *)((uint32_t)*hccr +
47 			HC_LENGTH(ehci_readl(&(*hccr)->cr_capbase)));
48 
49 	return 0;
50 }
51 
52 int ehci_hcd_stop(int index)
53 {
54 	at91_pmc_t *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
55 	ulong start_time, tmp_time;
56 
57 	/* Disable USB Host Clock */
58 	writel(1 << ATMEL_ID_UHPHS, &pmc->pcdr);
59 
60 	start_time = get_timer(0);
61 	/* Disable UTMI PLL */
62 	writel(readl(&pmc->uckr) & ~AT91_PMC_UPLLEN, &pmc->uckr);
63 	while ((readl(&pmc->sr) & AT91_PMC_LOCKU) == AT91_PMC_LOCKU) {
64 		WATCHDOG_RESET();
65 		tmp_time = get_timer(0);
66 		if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
67 			printf("ERROR: failed to stop UPLL\n");
68 			return -1;
69 		}
70 	}
71 
72 	return 0;
73 }
74