xref: /openbmc/linux/drivers/net/ethernet/chelsio/cxgb/espi.c (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)

// SPDX-License-Identifier: GPL-2.0-only
/*****************************************************************************
 *                                                                           *
 * File: espi.c                                                              *
 * $Revision: 1.14 $                                                         *
 * $Date: 2005/05/14 00:59:32 $                                              *
 * Description:                                                              *
 *  Ethernet SPI functionality.                                              *
 *  part of the Chelsio 10Gb Ethernet Driver.                                *
 *                                                                           *
 *                                                                           *
 * http://www.chelsio.com                                                    *
 *                                                                           *
 * Copyright (c) 2003 - 2005 Chelsio Communications, Inc.                    *
 * All rights reserved.                                                      *
 *                                                                           *
 * Maintainers: maintainers@chelsio.com                                      *
 *                                                                           *
 * Authors: Dimitrios Michailidis   <dm@chelsio.com>                         *
 *          Tina Yang               <tainay@chelsio.com>                     *
 *          Felix Marti             <felix@chelsio.com>                      *
 *          Scott Bardone           <sbardone@chelsio.com>                   *
 *          Kurt Ottaway            <kottaway@chelsio.com>                   *
 *          Frank DiMambro          <frank@chelsio.com>                      *
 *                                                                           *
 * History:                                                                  *
 *                                                                           *
 ****************************************************************************/

#include "common.h"
#include "regs.h"
#include "espi.h"

struct peespi {
	adapter_t *adapter;
	struct espi_intr_counts intr_cnt;
	u32 misc_ctrl;
	spinlock_t lock;
};

#define ESPI_INTR_MASK (F_DIP4ERR | F_RXDROP | F_TXDROP | F_RXOVERFLOW | \
			F_RAMPARITYERR | F_DIP2PARITYERR)
#define MON_MASK  (V_MONITORED_PORT_NUM(3) | F_MONITORED_DIRECTION \
		   | F_MONITORED_INTERFACE)

#define TRICN_CNFG 14
#define TRICN_CMD_READ  0x11
#define TRICN_CMD_WRITE 0x21
#define TRICN_CMD_ATTEMPTS 10

static int tricn_write(adapter_t *adapter, int bundle_addr, int module_addr,
		       int ch_addr, int reg_offset, u32 wr_data)
{
	int busy, attempts = TRICN_CMD_ATTEMPTS;

	writel(V_WRITE_DATA(wr_data) |
	       V_REGISTER_OFFSET(reg_offset) |
	       V_CHANNEL_ADDR(ch_addr) | V_MODULE_ADDR(module_addr) |
	       V_BUNDLE_ADDR(bundle_addr) |
	       V_SPI4_COMMAND(TRICN_CMD_WRITE),
	       adapter->regs + A_ESPI_CMD_ADDR);
	writel(0, adapter->regs + A_ESPI_GOSTAT);

	do {
		busy = readl(adapter->regs + A_ESPI_GOSTAT) & F_ESPI_CMD_BUSY;
	} while (busy && --attempts);

	if (busy)
		pr_err("%s: TRICN write timed out\n", adapter->name);

	return busy;
}

static int tricn_init(adapter_t *adapter)
{
	int i, sme = 1;

	if (!(readl(adapter->regs + A_ESPI_RX_RESET)  & F_RX_CLK_STATUS)) {
		pr_err("%s: ESPI clock not ready\n", adapter->name);
		return -1;
	}

	writel(F_ESPI_RX_CORE_RST, adapter->regs + A_ESPI_RX_RESET);

	if (sme) {
		tricn_write(adapter, 0, 0, 0, TRICN_CNFG, 0x81);
		tricn_write(adapter, 0, 1, 0, TRICN_CNFG, 0x81);
		tricn_write(adapter, 0, 2, 0, TRICN_CNFG, 0x81);
	}
	for (i = 1; i <= 8; i++)
		tricn_write(adapter, 0, 0, i, TRICN_CNFG, 0xf1);
	for (i = 1; i <= 2; i++)
		tricn_write(adapter, 0, 1, i, TRICN_CNFG, 0xf1);
	for (i = 1; i <= 3; i++)
		tricn_write(adapter, 0, 2, i, TRICN_CNFG, 0xe1);
	tricn_write(adapter, 0, 2, 4, TRICN_CNFG, 0xf1);
	tricn_write(adapter, 0, 2, 5, TRICN_CNFG, 0xe1);
	tricn_write(adapter, 0, 2, 6, TRICN_CNFG, 0xf1);
	tricn_write(adapter, 0, 2, 7, TRICN_CNFG, 0x80);
	tricn_write(adapter, 0, 2, 8, TRICN_CNFG, 0xf1);

	writel(F_ESPI_RX_CORE_RST | F_ESPI_RX_LNK_RST,
	       adapter->regs + A_ESPI_RX_RESET);

	return 0;
}

void t1_espi_intr_enable(struct peespi *espi)
{
	u32 enable, pl_intr = readl(espi->adapter->regs + A_PL_ENABLE);

	/*
	 * Cannot enable ESPI interrupts on T1B because HW asserts the
	 * interrupt incorrectly, namely the driver gets ESPI interrupts
	 * but no data is actually dropped (can verify this reading the ESPI
	 * drop registers).  Also, once the ESPI interrupt is asserted it
	 * cannot be cleared (HW bug).
	 */
	enable = t1_is_T1B(espi->adapter) ? 0 : ESPI_INTR_MASK;
	writel(enable, espi->adapter->regs + A_ESPI_INTR_ENABLE);
	writel(pl_intr | F_PL_INTR_ESPI, espi->adapter->regs + A_PL_ENABLE);
}

void t1_espi_intr_clear(struct peespi *espi)
{
	readl(espi->adapter->regs + A_ESPI_DIP2_ERR_COUNT);
	writel(0xffffffff, espi->adapter->regs + A_ESPI_INTR_STATUS);
	writel(F_PL_INTR_ESPI, espi->adapter->regs + A_PL_CAUSE);
}

void t1_espi_intr_disable(struct peespi *espi)
{
	u32 pl_intr = readl(espi->adapter->regs + A_PL_ENABLE);

	writel(0, espi->adapter->regs + A_ESPI_INTR_ENABLE);
	writel(pl_intr & ~F_PL_INTR_ESPI, espi->adapter->regs + A_PL_ENABLE);
}

int t1_espi_intr_handler(struct peespi *espi)
{
	u32 status = readl(espi->adapter->regs + A_ESPI_INTR_STATUS);

	if (status & F_DIP4ERR)
		espi->intr_cnt.DIP4_err++;
	if (status & F_RXDROP)
		espi->intr_cnt.rx_drops++;
	if (status & F_TXDROP)
		espi->intr_cnt.tx_drops++;
	if (status & F_RXOVERFLOW)
		espi->intr_cnt.rx_ovflw++;
	if (status & F_RAMPARITYERR)
		espi->intr_cnt.parity_err++;
	if (status & F_DIP2PARITYERR) {
		espi->intr_cnt.DIP2_parity_err++;

		/*
		 * Must read the error count to clear the interrupt
		 * that it causes.
		 */
		readl(espi->adapter->regs + A_ESPI_DIP2_ERR_COUNT);
	}

	/*
	 * For T1B we need to write 1 to clear ESPI interrupts.  For T2+ we
	 * write the status as is.
	 */
	if (status && t1_is_T1B(espi->adapter))
		status = 1;
	writel(status, espi->adapter->regs + A_ESPI_INTR_STATUS);
	return 0;
}

const struct espi_intr_counts *t1_espi_get_intr_counts(struct peespi *espi)
{
	return &espi->intr_cnt;
}

static void espi_setup_for_pm3393(adapter_t *adapter)
{
	u32 wmark = t1_is_T1B(adapter) ? 0x4000 : 0x3200;

	writel(0x1f4, adapter->regs + A_ESPI_SCH_TOKEN0);
	writel(0x1f4, adapter->regs + A_ESPI_SCH_TOKEN1);
	writel(0x1f4, adapter->regs + A_ESPI_SCH_TOKEN2);
	writel(0x1f4, adapter->regs + A_ESPI_SCH_TOKEN3);
	writel(0x100, adapter->regs + A_ESPI_RX_FIFO_ALMOST_EMPTY_WATERMARK);
	writel(wmark, adapter->regs + A_ESPI_RX_FIFO_ALMOST_FULL_WATERMARK);
	writel(3, adapter->regs + A_ESPI_CALENDAR_LENGTH);
	writel(0x08000008, adapter->regs + A_ESPI_TRAIN);
	writel(V_RX_NPORTS(1) | V_TX_NPORTS(1), adapter->regs + A_PORT_CONFIG);
}

static void espi_setup_for_vsc7321(adapter_t *adapter)
{
	writel(0x1f4, adapter->regs + A_ESPI_SCH_TOKEN0);
	writel(0x1f401f4, adapter->regs + A_ESPI_SCH_TOKEN1);
	writel(0x1f4, adapter->regs + A_ESPI_SCH_TOKEN2);
	writel(0xa00, adapter->regs + A_ESPI_RX_FIFO_ALMOST_FULL_WATERMARK);
	writel(0x1ff, adapter->regs + A_ESPI_RX_FIFO_ALMOST_EMPTY_WATERMARK);
	writel(1, adapter->regs + A_ESPI_CALENDAR_LENGTH);
	writel(V_RX_NPORTS(4) | V_TX_NPORTS(4), adapter->regs + A_PORT_CONFIG);

	writel(0x08000008, adapter->regs + A_ESPI_TRAIN);
}

/*
 * Note that T1B requires at least 2 ports for IXF1010 due to a HW bug.
 */
static void espi_setup_for_ixf1010(adapter_t *adapter, int nports)
{
	writel(1, adapter->regs + A_ESPI_CALENDAR_LENGTH);
	if (nports == 4) {
		if (is_T2(adapter)) {
			writel(0xf00, adapter->regs + A_ESPI_RX_FIFO_ALMOST_FULL_WATERMARK);
			writel(0x3c0, adapter->regs + A_ESPI_RX_FIFO_ALMOST_EMPTY_WATERMARK);
		} else {
			writel(0x7ff, adapter->regs + A_ESPI_RX_FIFO_ALMOST_FULL_WATERMARK);
			writel(0x1ff, adapter->regs + A_ESPI_RX_FIFO_ALMOST_EMPTY_WATERMARK);
		}
	} else {
		writel(0x1fff, adapter->regs + A_ESPI_RX_FIFO_ALMOST_FULL_WATERMARK);
		writel(0x7ff, adapter->regs + A_ESPI_RX_FIFO_ALMOST_EMPTY_WATERMARK);
	}
	writel(V_RX_NPORTS(nports) | V_TX_NPORTS(nports), adapter->regs + A_PORT_CONFIG);

}

int t1_espi_init(struct peespi *espi, int mac_type, int nports)
{
	u32 status_enable_extra = 0;
	adapter_t *adapter = espi->adapter;

	/* Disable ESPI training.  MACs that can handle it enable it below. */
	writel(0, adapter->regs + A_ESPI_TRAIN);

	if (is_T2(adapter)) {
		writel(V_OUT_OF_SYNC_COUNT(4) |
		       V_DIP2_PARITY_ERR_THRES(3) |
		       V_DIP4_THRES(1), adapter->regs + A_ESPI_MISC_CONTROL);
		writel(nports == 4 ? 0x200040 : 0x1000080,
		       adapter->regs + A_ESPI_MAXBURST1_MAXBURST2);
	} else
		writel(0x800100, adapter->regs + A_ESPI_MAXBURST1_MAXBURST2);

	if (mac_type == CHBT_MAC_PM3393)
		espi_setup_for_pm3393(adapter);
	else if (mac_type == CHBT_MAC_VSC7321)
		espi_setup_for_vsc7321(adapter);
	else if (mac_type == CHBT_MAC_IXF1010) {
		status_enable_extra = F_INTEL1010MODE;
		espi_setup_for_ixf1010(adapter, nports);
	} else
		return -1;

	writel(status_enable_extra | F_RXSTATUSENABLE,
	       adapter->regs + A_ESPI_FIFO_STATUS_ENABLE);

	if (is_T2(adapter)) {
		tricn_init(adapter);
		/*
		 * Always position the control at the 1st port egress IN
		 * (sop,eop) counter to reduce PIOs for T/N210 workaround.
		 */
		espi->misc_ctrl = readl(adapter->regs + A_ESPI_MISC_CONTROL);
		espi->misc_ctrl &= ~MON_MASK;
		espi->misc_ctrl |= F_MONITORED_DIRECTION;
		if (adapter->params.nports == 1)
			espi->misc_ctrl |= F_MONITORED_INTERFACE;
		writel(espi->misc_ctrl, adapter->regs + A_ESPI_MISC_CONTROL);
		spin_lock_init(&espi->lock);
	}

	return 0;
}

void t1_espi_destroy(struct peespi *espi)
{
	kfree(espi);
}

struct peespi *t1_espi_create(adapter_t *adapter)
{
	struct peespi *espi = kzalloc(sizeof(*espi), GFP_KERNEL);

	if (espi)
		espi->adapter = adapter;
	return espi;
}

#if 0
void t1_espi_set_misc_ctrl(adapter_t *adapter, u32 val)
{
	struct peespi *espi = adapter->espi;

	if (!is_T2(adapter))
		return;
	spin_lock(&espi->lock);
	espi->misc_ctrl = (val & ~MON_MASK) |
			  (espi->misc_ctrl & MON_MASK);
	writel(espi->misc_ctrl, adapter->regs + A_ESPI_MISC_CONTROL);
	spin_unlock(&espi->lock);
}
#endif  /*  0  */

u32 t1_espi_get_mon(adapter_t *adapter, u32 addr, u8 wait)
{
	struct peespi *espi = adapter->espi;
	u32 sel;

	if (!is_T2(adapter))
		return 0;

	sel = V_MONITORED_PORT_NUM((addr & 0x3c) >> 2);
	if (!wait) {
		if (!spin_trylock(&espi->lock))
			return 0;
	} else
		spin_lock(&espi->lock);

	if ((sel != (espi->misc_ctrl & MON_MASK))) {
		writel(((espi->misc_ctrl & ~MON_MASK) | sel),
		       adapter->regs + A_ESPI_MISC_CONTROL);
		sel = readl(adapter->regs + A_ESPI_SCH_TOKEN3);
		writel(espi->misc_ctrl, adapter->regs + A_ESPI_MISC_CONTROL);
	} else
		sel = readl(adapter->regs + A_ESPI_SCH_TOKEN3);
	spin_unlock(&espi->lock);
	return sel;
}

/*
 * This function is for T204 only.
 * compare with t1_espi_get_mon(), it reads espiInTxSop[0 ~ 3] in
 * one shot, since there is no per port counter on the out side.
 */
int t1_espi_get_mon_t204(adapter_t *adapter, u32 *valp, u8 wait)
{
	struct peespi *espi = adapter->espi;
	u8 i, nport = (u8)adapter->params.nports;

	if (!wait) {
		if (!spin_trylock(&espi->lock))
			return -1;
	} else
		spin_lock(&espi->lock);

	if ((espi->misc_ctrl & MON_MASK) != F_MONITORED_DIRECTION) {
		espi->misc_ctrl = (espi->misc_ctrl & ~MON_MASK) |
					F_MONITORED_DIRECTION;
		writel(espi->misc_ctrl, adapter->regs + A_ESPI_MISC_CONTROL);
	}
	for (i = 0 ; i < nport; i++, valp++) {
		if (i) {
			writel(espi->misc_ctrl | V_MONITORED_PORT_NUM(i),
			       adapter->regs + A_ESPI_MISC_CONTROL);
		}
		*valp = readl(adapter->regs + A_ESPI_SCH_TOKEN3);
	}

	writel(espi->misc_ctrl, adapter->regs + A_ESPI_MISC_CONTROL);
	spin_unlock(&espi->lock);
	return 0;
}