/** * e1000_shift_in_mdi_bits_82543 - Shift data bits in from the PHY * @hw: pointer to the HW structure * * In order to read a register from the PHY, we need to shift 18 bits * in from the PHY. Bits are "shifted in" by raising the clock input to * the PHY (setting the MDC bit), and then reading the value of the data out * MDIO bit. **/ static u16 e1000_shift_in_mdi_bits_82543(struct e1000_hw *hw) { u32 ctrl; u16 data = 0; u8 i; /* * In order to read a register from the PHY, we need to shift in a * total of 18 bits from the PHY. The first two bit (turnaround) * times are used to avoid contention on the MDIO pin when a read * operation is performed. These two bits are ignored by us and * thrown away. Bits are "shifted in" by raising the input to the * Management Data Clock (setting the MDC bit) and then reading the * value of the MDIO bit. */ ctrl = E1000_READ_REG(hw, E1000_CTRL); /* * Clear MDIO_DIR (SWDPIO1) to indicate this bit is to be used as * input. */ ctrl &= ~E1000_CTRL_MDIO_DIR; ctrl &= ~E1000_CTRL_MDIO; E1000_WRITE_REG(hw, E1000_CTRL, ctrl); E1000_WRITE_FLUSH(hw); /* * Raise and lower the clock before reading in the data. This accounts * for the turnaround bits. The first clock occurred when we clocked * out the last bit of the Register Address. */ e1000_raise_mdi_clk_82543(hw, &ctrl); e1000_lower_mdi_clk_82543(hw, &ctrl); for (data = 0, i = 0; i < 16; i++) { data <<= 1; e1000_raise_mdi_clk_82543(hw, &ctrl); ctrl = E1000_READ_REG(hw, E1000_CTRL); /* Check to see if we shifted in a "1". */ if (ctrl & E1000_CTRL_MDIO) data |= 1; e1000_lower_mdi_clk_82543(hw, &ctrl); } e1000_raise_mdi_clk_82543(hw, &ctrl); e1000_lower_mdi_clk_82543(hw, &ctrl); return data; }
/** * e1000_shift_out_mdi_bits_82543 - Shift data bits our to the PHY * @hw: pointer to the HW structure * @data: data to send to the PHY * @count: number of bits to shift out * * We need to shift 'count' bits out to the PHY. So, the value in the * "data" parameter will be shifted out to the PHY one bit at a time. * In order to do this, "data" must be broken down into bits. **/ STATIC void e1000_shift_out_mdi_bits_82543(struct e1000_hw *hw, u32 data, u16 count) { u32 ctrl, mask; /* * We need to shift "count" number of bits out to the PHY. So, the * value in the "data" parameter will be shifted out to the PHY one * bit at a time. In order to do this, "data" must be broken down * into bits. */ mask = 0x01; mask <<= (count - 1); ctrl = E1000_READ_REG(hw, E1000_CTRL); /* Set MDIO_DIR and MDC_DIR direction bits to be used as output pins. */ ctrl |= (E1000_CTRL_MDIO_DIR | E1000_CTRL_MDC_DIR); while (mask) { /* * A "1" is shifted out to the PHY by setting the MDIO bit to * "1" and then raising and lowering the Management Data Clock. * A "0" is shifted out to the PHY by setting the MDIO bit to * "0" and then raising and lowering the clock. */ if (data & mask) ctrl |= E1000_CTRL_MDIO; else ctrl &= ~E1000_CTRL_MDIO; E1000_WRITE_REG(hw, E1000_CTRL, ctrl); E1000_WRITE_FLUSH(hw); usec_delay(10); e1000_raise_mdi_clk_82543(hw, &ctrl); e1000_lower_mdi_clk_82543(hw, &ctrl); mask >>= 1; } }