diff options
| author | Al Cooper <alcooperx@gmail.com> | 2020-01-03 13:17:59 -0500 |
|---|---|---|
| committer | Kishon Vijay Abraham I <kishon@ti.com> | 2020-01-08 12:58:06 +0530 |
| commit | dc9aa43c43668481089c48135707ec3f8f5b2e19 (patch) | |
| tree | 99f9d24d585487209ccf87856a9fb879c8a386d7 /drivers/phy | |
| parent | d0312fdbf3e1dc34bc370b17fee290921cf9b814 (diff) | |
phy: usb: EHCI DMA may lose a burst of DMA data for 7255xA0 family
When the EHCI controller received a 512 byte USB packet that
had to be broken into 2 256 byte bursts across the SCB bus AND
there was a following 512 byte USB packet, the second burst of
data from the first packet was sometimes being lost. If the
burst size was changed to 128 bytes via the EBR_SCB_SIZE field
in the USB_CTRL_EBRIDGE register we'd see the 4th 128 byte burst
of the first packet being lost. This problem became much worse
if other threads were running that accessed memory, like a memcpy
test. Setting the EBR_SCB_SIZE to 512, which prevents breaking
the EHCI USB packet (max size of 512 bytes) into bursts, fixed
the problem.
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Diffstat (limited to 'drivers/phy')
| -rw-r--r-- | drivers/phy/broadcom/phy-brcm-usb-init.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/phy/broadcom/phy-brcm-usb-init.c b/drivers/phy/broadcom/phy-brcm-usb-init.c index 91b5b09589d6..bd473d12ab28 100644 --- a/drivers/phy/broadcom/phy-brcm-usb-init.c +++ b/drivers/phy/broadcom/phy-brcm-usb-init.c @@ -42,6 +42,7 @@ #define USB_CTRL_PLL_CTL_PLL_IDDQ_PWRDN_MASK 0x80000000 /* option */ #define USB_CTRL_EBRIDGE 0x0c #define USB_CTRL_EBRIDGE_ESTOP_SCB_REQ_MASK 0x00020000 /* option */ +#define USB_CTRL_EBRIDGE_EBR_SCB_SIZE_MASK 0x00000f80 /* option */ #define USB_CTRL_OBRIDGE 0x10 #define USB_CTRL_OBRIDGE_LS_KEEP_ALIVE_MASK 0x08000000 #define USB_CTRL_MDIO 0x14 @@ -176,6 +177,7 @@ static const struct id_to_type id_to_type_table[] = { { 0x33900000, BRCM_FAMILY_3390A0 }, { 0x72500010, BRCM_FAMILY_7250B0 }, { 0x72600000, BRCM_FAMILY_7260A0 }, + { 0x72550000, BRCM_FAMILY_7260A0 }, { 0x72680000, BRCM_FAMILY_7271A0 }, { 0x72710000, BRCM_FAMILY_7271A0 }, { 0x73640000, BRCM_FAMILY_7364A0 }, @@ -948,6 +950,17 @@ void brcm_usb_init_eohci(struct brcm_usb_init_params *params) if (params->selected_family == BRCM_FAMILY_7271A0) /* Enable LS keep alive fix for certain keyboards */ USB_CTRL_SET(ctrl, OBRIDGE, LS_KEEP_ALIVE); + + if (params->family_id == 0x72550000) { + /* + * Make the burst size 512 bytes to fix a hardware bug + * on the 7255a0. See HW7255-24. + */ + reg = brcmusb_readl(USB_CTRL_REG(ctrl, EBRIDGE)); + reg &= ~USB_CTRL_MASK(EBRIDGE, EBR_SCB_SIZE); + reg |= 0x800; + brcmusb_writel(reg, USB_CTRL_REG(ctrl, EBRIDGE)); + } } void brcm_usb_init_xhci(struct brcm_usb_init_params *params) |