drivers/usb/host/ehci-atmel.c

   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, struct ehci_hccr **hccr, struct ehci_hcor **hcor)
  25 {
  26         at91_pmc_t *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
  27         ulong start_time, tmp_time;
  28
  29         start_time = get_timer(0);
  30         /* Enable UTMI PLL */
  31         writel(AT91_PMC_UPLLEN | AT91_PMC_BIASEN, &pmc->uckr);
  32         while ((readl(&pmc->sr) & AT91_PMC_LOCKU) != AT91_PMC_LOCKU) {
  33                 WATCHDOG_RESET();
  34                 tmp_time = get_timer(0);
  35                 if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
  36                         printf("ERROR: failed to enable UPLL\n");
  37                         return -1;
  38                 }
  39         }
  40
  41         /* Enable USB Host clock */
  42         writel(1 << ATMEL_ID_UHPHS, &pmc->pcer);
  43
  44         *hccr = (struct ehci_hccr *)ATMEL_BASE_EHCI;
  45         *hcor = (struct ehci_hcor *)((uint32_t)*hccr +
  46                         HC_LENGTH(ehci_readl(&(*hccr)->cr_capbase)));
  47
  48         return 0;
  49 }
  50
  51 int ehci_hcd_stop(int index)
  52 {
  53         at91_pmc_t *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
  54         ulong start_time, tmp_time;
  55
  56         /* Disable USB Host Clock */
  57         writel(1 << ATMEL_ID_UHPHS, &pmc->pcdr);
  58
  59         start_time = get_timer(0);
  60         /* Disable UTMI PLL */
  61         writel(readl(&pmc->uckr) & ~AT91_PMC_UPLLEN, &pmc->uckr);
  62         while ((readl(&pmc->sr) & AT91_PMC_LOCKU) == AT91_PMC_LOCKU) {
  63                 WATCHDOG_RESET();
  64                 tmp_time = get_timer(0);
  65                 if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
  66                         printf("ERROR: failed to stop UPLL\n");
  67                         return -1;
  68                 }
  69         }
  70
  71         return 0;
  72 }