git.openwrt.org Git - openwrt/openwrt.git/blob

   1 From dc9aa43c43668481089c48135707ec3f8f5b2e19 Mon Sep 17 00:00:00 2001
   2 From: Al Cooper <alcooperx@gmail.com>
   3 Date: Fri, 3 Jan 2020 13:17:59 -0500
   4 Subject: [PATCH] phy: usb: EHCI DMA may lose a burst of DMA data for 7255xA0
   5  family
   6
   7 When the EHCI controller received a 512 byte USB packet that
   8 had to be broken into 2 256 byte bursts across the SCB bus AND
   9 there was a following 512 byte USB packet, the second burst of
  10 data from the first packet was sometimes being lost. If the
  11 burst size was changed to 128 bytes via the EBR_SCB_SIZE field
  12 in the USB_CTRL_EBRIDGE register we'd see the 4th 128 byte burst
  13 of the first packet being lost. This problem became much worse
  14 if other threads were running that accessed memory, like a memcpy
  15 test. Setting the EBR_SCB_SIZE to 512, which prevents breaking
  16 the EHCI USB packet (max size of 512 bytes) into bursts, fixed
  17 the problem.
  18
  19 Signed-off-by: Al Cooper <alcooperx@gmail.com>
  20 Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
  21 Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
  22 ---
  23  drivers/phy/broadcom/phy-brcm-usb-init.c | 13 +++++++++++++
  24  1 file changed, 13 insertions(+)
  25
  26 --- a/drivers/phy/broadcom/phy-brcm-usb-init.c
  27 +++ b/drivers/phy/broadcom/phy-brcm-usb-init.c
  28 @@ -42,6 +42,7 @@
  29  #define   USB_CTRL_PLL_CTL_PLL_IDDQ_PWRDN_MASK         0x80000000 /* option */
  30  #define USB_CTRL_EBRIDGE               0x0c
  31  #define   USB_CTRL_EBRIDGE_ESTOP_SCB_REQ_MASK          0x00020000 /* option */
  32 +#define   USB_CTRL_EBRIDGE_EBR_SCB_SIZE_MASK           0x00000f80 /* option */
  33  #define USB_CTRL_OBRIDGE               0x10
  34  #define   USB_CTRL_OBRIDGE_LS_KEEP_ALIVE_MASK          0x08000000
  35  #define USB_CTRL_MDIO                  0x14
  36 @@ -176,6 +177,7 @@ static const struct id_to_type id_to_typ
  37         { 0x33900000, BRCM_FAMILY_3390A0 },
  38         { 0x72500010, BRCM_FAMILY_7250B0 },
  39         { 0x72600000, BRCM_FAMILY_7260A0 },
  40 +       { 0x72550000, BRCM_FAMILY_7260A0 },
  41         { 0x72680000, BRCM_FAMILY_7271A0 },
  42         { 0x72710000, BRCM_FAMILY_7271A0 },
  43         { 0x73640000, BRCM_FAMILY_7364A0 },
  44 @@ -948,6 +950,17 @@ void brcm_usb_init_eohci(struct brcm_usb
  45         if (params->selected_family == BRCM_FAMILY_7271A0)
  46                 /* Enable LS keep alive fix for certain keyboards */
  47                 USB_CTRL_SET(ctrl, OBRIDGE, LS_KEEP_ALIVE);
  48 +
  49 +       if (params->family_id == 0x72550000) {
  50 +               /*
  51 +                * Make the burst size 512 bytes to fix a hardware bug
  52 +                * on the 7255a0. See HW7255-24.
  53 +                */
  54 +               reg = brcmusb_readl(USB_CTRL_REG(ctrl, EBRIDGE));
  55 +               reg &= ~USB_CTRL_MASK(EBRIDGE, EBR_SCB_SIZE);
  56 +               reg |= 0x800;
  57 +               brcmusb_writel(reg, USB_CTRL_REG(ctrl, EBRIDGE));
  58 +       }
  59  }
  60
  61  void brcm_usb_init_xhci(struct brcm_usb_init_params *params)