// SPDX-License-Identifier: GPL-2.0-only
/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2018 Solarflare Communications Inc.
 * Copyright 2019-2020 Xilinx Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */

#include "ef100_nic.h"
#include "efx_common.h"
#include "efx_channels.h"
#include "io.h"
#include "selftest.h"
#include "ef100_regs.h"
#include "mcdi.h"
#include "mcdi_pcol.h"
#include "mcdi_port_common.h"
#include "mcdi_functions.h"
#include "mcdi_filters.h"
#include "ef100_rx.h"
#include "ef100_tx.h"
#include "ef100_netdev.h"

#define EF100_MAX_VIS 4096
#define EF100_NUM_MCDI_BUFFERS	1
#define MCDI_BUF_LEN (8 + MCDI_CTL_SDU_LEN_MAX)

#define EF100_RESET_PORT ((ETH_RESET_MAC | ETH_RESET_PHY) << ETH_RESET_SHARED_SHIFT)

/*	MCDI
 */
static u8 *ef100_mcdi_buf(struct efx_nic *efx, u8 bufid, dma_addr_t *dma_addr)
{
	struct ef100_nic_data *nic_data = efx->nic_data;

	if (dma_addr)
		*dma_addr = nic_data->mcdi_buf.dma_addr +
			    bufid * ALIGN(MCDI_BUF_LEN, 256);
	return nic_data->mcdi_buf.addr + bufid * ALIGN(MCDI_BUF_LEN, 256);
}

static int ef100_get_warm_boot_count(struct efx_nic *efx)
{
	efx_dword_t reg;

	efx_readd(efx, &reg, efx_reg(efx, ER_GZ_MC_SFT_STATUS));

	if (EFX_DWORD_FIELD(reg, EFX_DWORD_0) == 0xffffffff) {
		netif_err(efx, hw, efx->net_dev, "Hardware unavailable\n");
		efx->state = STATE_DISABLED;
		return -ENETDOWN;
	} else {
		return EFX_DWORD_FIELD(reg, EFX_WORD_1) == 0xb007 ?
			EFX_DWORD_FIELD(reg, EFX_WORD_0) : -EIO;
	}
}

static void ef100_mcdi_request(struct efx_nic *efx,
			       const efx_dword_t *hdr, size_t hdr_len,
			       const efx_dword_t *sdu, size_t sdu_len)
{
	dma_addr_t dma_addr;
	u8 *pdu = ef100_mcdi_buf(efx, 0, &dma_addr);

	memcpy(pdu, hdr, hdr_len);
	memcpy(pdu + hdr_len, sdu, sdu_len);
	wmb();

	/* The hardware provides 'low' and 'high' (doorbell) registers
	 * for passing the 64-bit address of an MCDI request to
	 * firmware.  However the dwords are swapped by firmware.  The
	 * least significant bits of the doorbell are then 0 for all
	 * MCDI requests due to alignment.
	 */
	_efx_writed(efx, cpu_to_le32((u64)dma_addr >> 32),  efx_reg(efx, ER_GZ_MC_DB_LWRD));
	_efx_writed(efx, cpu_to_le32((u32)dma_addr),  efx_reg(efx, ER_GZ_MC_DB_HWRD));
}

static bool ef100_mcdi_poll_response(struct efx_nic *efx)
{
	const efx_dword_t hdr =
		*(const efx_dword_t *)(ef100_mcdi_buf(efx, 0, NULL));

	rmb();
	return EFX_DWORD_FIELD(hdr, MCDI_HEADER_RESPONSE);
}

static void ef100_mcdi_read_response(struct efx_nic *efx,
				     efx_dword_t *outbuf, size_t offset,
				     size_t outlen)
{
	const u8 *pdu = ef100_mcdi_buf(efx, 0, NULL);

	memcpy(outbuf, pdu + offset, outlen);
}

static int ef100_mcdi_poll_reboot(struct efx_nic *efx)
{
	struct ef100_nic_data *nic_data = efx->nic_data;
	int rc;

	rc = ef100_get_warm_boot_count(efx);
	if (rc < 0) {
		/* The firmware is presumably in the process of
		 * rebooting.  However, we are supposed to report each
		 * reboot just once, so we must only do that once we
		 * can read and store the updated warm boot count.
		 */
		return 0;
	}

	if (rc == nic_data->warm_boot_count)
		return 0;

	nic_data->warm_boot_count = rc;

	return -EIO;
}

static void ef100_mcdi_reboot_detected(struct efx_nic *efx)
{
}

/*	Event handling
 */
static int ef100_ev_probe(struct efx_channel *channel)
{
	/* Allocate an extra descriptor for the QMDA status completion entry */
	return efx_nic_alloc_buffer(channel->efx, &channel->eventq.buf,
				    (channel->eventq_mask + 2) *
				    sizeof(efx_qword_t),
				    GFP_KERNEL);
}

static irqreturn_t ef100_msi_interrupt(int irq, void *dev_id)
{
	struct efx_msi_context *context = dev_id;
	struct efx_nic *efx = context->efx;

	netif_vdbg(efx, intr, efx->net_dev,
		   "IRQ %d on CPU %d\n", irq, raw_smp_processor_id());

	if (likely(READ_ONCE(efx->irq_soft_enabled))) {
		/* Note test interrupts */
		if (context->index == efx->irq_level)
			efx->last_irq_cpu = raw_smp_processor_id();

		/* Schedule processing of the channel */
		efx_schedule_channel_irq(efx->channel[context->index]);
	}

	return IRQ_HANDLED;
}

static int ef100_phy_probe(struct efx_nic *efx)
{
	/* stub: allocate the phy_data */
	efx->phy_data = kzalloc(sizeof(struct efx_mcdi_phy_data), GFP_KERNEL);
	if (!efx->phy_data)
		return -ENOMEM;

	return 0;
}

/*	Other
 */

static enum reset_type ef100_map_reset_reason(enum reset_type reason)
{
	if (reason == RESET_TYPE_TX_WATCHDOG)
		return reason;
	return RESET_TYPE_DISABLE;
}

static int ef100_map_reset_flags(u32 *flags)
{
	/* Only perform a RESET_TYPE_ALL because we don't support MC_REBOOTs */
	if ((*flags & EF100_RESET_PORT)) {
		*flags &= ~EF100_RESET_PORT;
		return RESET_TYPE_ALL;
	}
	if (*flags & ETH_RESET_MGMT) {
		*flags &= ~ETH_RESET_MGMT;
		return RESET_TYPE_DISABLE;
	}

	return -EINVAL;
}

static int ef100_reset(struct efx_nic *efx, enum reset_type reset_type)
{
	int rc;

	dev_close(efx->net_dev);

	if (reset_type == RESET_TYPE_TX_WATCHDOG) {
		netif_device_attach(efx->net_dev);
		__clear_bit(reset_type, &efx->reset_pending);
		rc = dev_open(efx->net_dev, NULL);
	} else if (reset_type == RESET_TYPE_ALL) {
		netif_device_attach(efx->net_dev);

		rc = dev_open(efx->net_dev, NULL);
	} else {
		rc = 1;	/* Leave the device closed */
	}
	return rc;
}

/*	NIC level access functions
 */
const struct efx_nic_type ef100_pf_nic_type = {
	.revision = EFX_REV_EF100,
	.is_vf = false,
	.probe = ef100_probe_pf,
	.mcdi_max_ver = 2,
	.mcdi_request = ef100_mcdi_request,
	.mcdi_poll_response = ef100_mcdi_poll_response,
	.mcdi_read_response = ef100_mcdi_read_response,
	.mcdi_poll_reboot = ef100_mcdi_poll_reboot,
	.mcdi_reboot_detected = ef100_mcdi_reboot_detected,
	.irq_enable_master = efx_port_dummy_op_void,
	.irq_disable_non_ev = efx_port_dummy_op_void,
	.push_irq_moderation = efx_channel_dummy_op_void,
	.min_interrupt_mode = EFX_INT_MODE_MSIX,
	.map_reset_reason = ef100_map_reset_reason,
	.map_reset_flags = ef100_map_reset_flags,
	.reset = ef100_reset,

	.ev_probe = ef100_ev_probe,
	.irq_handle_msi = ef100_msi_interrupt,

	/* Per-type bar/size configuration not used on ef100. Location of
	 * registers is defined by extended capabilities.
	 */
	.mem_bar = NULL,
	.mem_map_size = NULL,

};

/*	NIC probe and remove
 */
static int ef100_probe_main(struct efx_nic *efx)
{
	unsigned int bar_size = resource_size(&efx->pci_dev->resource[efx->mem_bar]);
	struct net_device *net_dev = efx->net_dev;
	struct ef100_nic_data *nic_data;
	int i, rc;

	if (WARN_ON(bar_size == 0))
		return -EIO;

	nic_data = kzalloc(sizeof(*nic_data), GFP_KERNEL);
	if (!nic_data)
		return -ENOMEM;
	efx->nic_data = nic_data;
	nic_data->efx = efx;
	net_dev->features |= efx->type->offload_features;
	net_dev->hw_features |= efx->type->offload_features;

	/* we assume later that we can copy from this buffer in dwords */
	BUILD_BUG_ON(MCDI_CTL_SDU_LEN_MAX_V2 % 4);

	/* MCDI buffers must be 256 byte aligned. */
	rc = efx_nic_alloc_buffer(efx, &nic_data->mcdi_buf, MCDI_BUF_LEN,
				  GFP_KERNEL);
	if (rc)
		goto fail;

	/* Get the MC's warm boot count.  In case it's rebooting right
	 * now, be prepared to retry.
	 */
	i = 0;
	for (;;) {
		rc = ef100_get_warm_boot_count(efx);
		if (rc >= 0)
			break;
		if (++i == 5)
			goto fail;
		ssleep(1);
	}
	nic_data->warm_boot_count = rc;

	/* In case we're recovering from a crash (kexec), we want to
	 * cancel any outstanding request by the previous user of this
	 * function.  We send a special message using the least
	 * significant bits of the 'high' (doorbell) register.
	 */
	_efx_writed(efx, cpu_to_le32(1), efx_reg(efx, ER_GZ_MC_DB_HWRD));

	/* Post-IO section. */

	rc = efx_mcdi_init(efx);
	if (!rc && efx->mcdi->fn_flags &
		   (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_NO_ACTIVE_PORT)) {
		netif_info(efx, probe, efx->net_dev,
			   "No network port on this PCI function");
		rc = -ENODEV;
	}
	if (rc)
		goto fail;

	efx->max_vis = EF100_MAX_VIS;

	rc = ef100_phy_probe(efx);
	if (rc)
		goto fail;

	rc = efx_init_channels(efx);
	if (rc)
		goto fail;

	rc = ef100_register_netdev(efx);
	if (rc)
		goto fail;

	return 0;
fail:
	return rc;
}

int ef100_probe_pf(struct efx_nic *efx)
{
	return ef100_probe_main(efx);
}

void ef100_remove(struct efx_nic *efx)
{
	struct ef100_nic_data *nic_data = efx->nic_data;

	ef100_unregister_netdev(efx);
	efx_fini_channels(efx);
	kfree(efx->phy_data);
	efx->phy_data = NULL;
	efx_mcdi_detach(efx);
	efx_mcdi_fini(efx);
	if (nic_data)
		efx_nic_free_buffer(efx, &nic_data->mcdi_buf);
	kfree(nic_data);
	efx->nic_data = NULL;
}