/*
* Generic library functions for the MSF (Media and Switch Fabric) unit
* found on the Intel IXP2400 network processor.
*
* Copyright (C) 2004, 2005 Lennert Buytenhek <buytenh@wantstofly.org>
* Dedicated to Marija Kulikova.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of the
* License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/arch/hardware.h>
#include <asm/arch/ixp2000-regs.h>
#include <asm/delay.h>
#include <asm/io.h>
#include "ixp2400-msf.h"
/*
* This is the Intel recommended PLL init procedure as described on
* page 340 of the IXP2400/IXP2800 Programmer's Reference Manual.
*/
static void ixp2400_pll_init(struct ixp2400_msf_parameters *mp)
{
int rx_dual_clock;
int tx_dual_clock;
u32 value;
/*
* If the RX mode is not 1x32, we have to enable both RX PLLs
* (#0 and #1.) The same thing for the TX direction.
*/
rx_dual_clock = !!(mp->rx_mode & IXP2400_RX_MODE_WIDTH_MASK);
tx_dual_clock = !!(mp->tx_mode & IXP2400_TX_MODE_WIDTH_MASK);
/*
* Read initial value.
*/
value = ixp2000_reg_read(IXP2000_MSF_CLK_CNTRL);
/*
* Put PLLs in powerdown and bypass mode.
*/
value |= 0x0000f0f0;
ixp2000_reg_write(IXP2000_MSF_CLK_CNTRL, value);
/*
* Set single or dual clock mode bits.
*/
value &= ~0x03000000;
value |= (rx_dual_clock << 24) | (tx_dual_clock << 25);
/*
* Set multipliers.
*/
value &= ~0x00ff0000;
value |= mp->rxclk01_multiplier << 16;
value |= mp->rxclk23_multiplier << 18;
value |= mp->txclk01_multiplier << 20;
value |= mp->txclk23_multiplier << 22;
/*
* And write value.
*/
ixp2000_reg_write(IXP2000_MSF_CLK_CNTRL, value);
/*
* Disable PLL bypass mode.
*/
value &= ~(0x00005000 | rx_dual_clock << 13 | tx_dual_clock << 15);
ixp2000_reg_write(IXP2000_MSF_CLK_CNTRL, value);
/*
* Turn on PLLs.
*/
value &= ~(0x00000050 | rx_dual_clock << 5 | tx_dual_clock << 7);
ixp2000_reg_write(IXP2000_MSF_CLK_CNTRL, value);
/*
* Wait for PLLs to lock. There are lock status bits, but IXP2400
* erratum #65 says that these lock bits should not be relied upon
* as they might not accurately reflect the true state of the PLLs.
*/
udelay(100);
}
/*
* Needed according to p480 of Programmer's Reference Manual.
*/
static void ixp2400_msf_free_rbuf_entries(struct ixp2400_msf_parameters *mp)
{
int size_bits;
int i;
/*
* Work around IXP2400 erratum #69 (silent RBUF-to-DRAM transfer
* corruption) in the Intel-recommended way: do not add the RBUF
* elements susceptible to corruption to the freelist.
*/
size_bits = mp->rx_mode & IXP2400_RX_MODE_RBUF_SIZE_MASK;
if (size_bits == IXP2400_RX_MODE_RBUF_SIZE_64) {
for (i = 1; i < 128; i++) {
if (i == 9 || i == 18 || i == 27)
continue;
ixp2000_reg_write(IXP2000_MSF_RBUF_ELEMENT_DONE, i);
}
} else if (size_bits == IXP2400_RX_MODE_RBUF_SIZE_128) {
for (i = 1; i < 64; i++) {
if (i == 4 || i == 9 || i == 13)
continue;
ixp2000_reg_write(IXP2000_MSF_RBUF_ELEMENT_DONE, i);
}
} else if (size_bits == IXP2400_RX_MODE_RBUF_SIZE_256) {
for (i = 1; i < 32; i++) {
if (i == 2 || i == 4 || i == 6)
continue;
ixp2000_reg_write(IXP2000_MSF_RBUF_ELEMENT_DONE, i);
}
}
}
static u32 ixp2400_msf_valid_channels(u32 reg)
{
u32 channels;
channels = 0;
switch (reg & IXP2400_RX_MODE_WIDTH_MASK) {
case IXP2400_RX_MODE_1x32:
channels = 0x1;
if (reg & IXP2400_RX_MODE_MPHY &&
!(reg & IXP2400_RX_MODE_MPHY_32))
channels = 0xf;
break;
case IXP2400_RX_MODE_2x16:
channels = 0x5;
break;
case IXP2400_RX_MODE_4x8:
channels = 0xf;
break;
case IXP2400_RX_MODE_1x16_2x8:
channels = 0xd;
break;
}
return channels;
}
static void ixp2400_msf_enable_rx(struct ixp2400_msf_parameters *mp)
{
u32 value;
value = ixp2000_reg_read(IXP2000_MSF_RX_CONTROL) & 0x0fffffff;
value |= ixp2400_msf_valid_channels(mp->rx_mode) << 28;
ixp2000_reg_write(IXP2000_MSF_RX_CONTROL, value);
}
static void ixp2400_msf_enable_tx(struct ixp2400_msf_parameters *mp)
{
u32 value;
value = ixp2000_reg_read(IXP2000_MSF_TX_CONTROL) & 0x0fffffff;
value |= ixp2400_msf_valid_channels(mp->tx_mode) << 28;
ixp2000_reg_write(IXP2000_MSF_TX_CONTROL, value);
}
void ixp2400_msf_init(struct ixp2400_msf_parameters *mp)
{
u32 value;
int i;
/*
* Init the RX/TX PLLs based on the passed parameter block.
*/
ixp2400_pll_init(mp);
/*
* Reset MSF. Bit 7 in IXP_RESET_0 resets the MSF.
*/
value = ixp2000_reg_read(IXP2000_RESET0);
ixp2000_reg_write(IXP2000_RESET0, value | 0x80);
ixp2000_reg_write(IXP2000_RESET0, value & ~0x80);
/*
* Initialise the RX section.
*/
ixp2000_reg_write(IXP2000_MSF_RX_MPHY_POLL_LIMIT, mp->rx_poll_ports - 1);
ixp2000_reg_write(IXP2000_MSF_RX_CONTROL, mp->rx_mode);
for (i = 0; i < 4; i++) {
ixp2000_reg_write(IXP2000_MSF_RX_UP_CONTROL_0 + i,
mp->rx_channel_mode[i]);
}
ixp2400_msf_free_rbuf_entries(mp);
ixp2400_msf_enable_rx(mp);
/*
* Initialise the TX section.
*/
ixp2000_reg_write(IXP2000_MSF_TX_MPHY_POLL_LIMIT, mp->tx_poll_ports - 1);
ixp2000_reg_write(IXP2000_MSF_TX_CONTROL, mp->tx_mode);
for (i = 0; i < 4; i++) {
ixp2000_reg_write(IXP2000_MSF_TX_UP_CONTROL_0 + i,
mp->tx_channel_mode[i]);
}
ixp2400_msf_enable_tx(mp);
}
