path: root/drivers/net/wireless/ath/wil6210/wmi.c

/*
 * Copyright (c) 2012 Qualcomm Atheros, Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <linux/etherdevice.h>
#include <linux/if_arp.h>

#include "wil6210.h"
#include "txrx.h"
#include "wmi.h"
#include "trace.h"

/**
 * WMI event receiving - theory of operations
 *
 * When firmware about to report WMI event, it fills memory area
 * in the mailbox and raises misc. IRQ. Thread interrupt handler invoked for
 * the misc IRQ, function @wmi_recv_cmd called by thread IRQ handler.
 *
 * @wmi_recv_cmd reads event, allocates memory chunk  and attaches it to the
 * event list @wil->pending_wmi_ev. Then, work queue @wil->wmi_wq wakes up
 * and handles events within the @wmi_event_worker. Every event get detached
 * from list, processed and deleted.
 *
 * Purpose for this mechanism is to release IRQ thread; otherwise,
 * if WMI event handling involves another WMI command flow, this 2-nd flow
 * won't be completed because of blocked IRQ thread.
 */

/**
 * Addressing - theory of operations
 *
 * There are several buses present on the WIL6210 card.
 * Same memory areas are visible at different address on
 * the different busses. There are 3 main bus masters:
 *  - MAC CPU (ucode)
 *  - User CPU (firmware)
 *  - AHB (host)
 *
 * On the PCI bus, there is one BAR (BAR0) of 2Mb size, exposing
 * AHB addresses starting from 0x880000
 *
 * Internally, firmware uses addresses that allows faster access but
 * are invisible from the host. To read from these addresses, alternative
 * AHB address must be used.
 *
 * Memory mapping
 * Linker address         PCI/Host address
 *                        0x880000 .. 0xa80000  2Mb BAR0
 * 0x800000 .. 0x807000   0x900000 .. 0x907000  28k DCCM
 * 0x840000 .. 0x857000   0x908000 .. 0x91f000  92k PERIPH
 */

/**
 * @fw_mapping provides memory remapping table
 */
static const struct {
	u32 from; /* linker address - from, inclusive */
	u32 to;   /* linker address - to, exclusive */
	u32 host; /* PCI/Host address - BAR0 + 0x880000 */
} fw_mapping[] = {
	{0x000000, 0x040000, 0x8c0000}, /* FW code RAM 256k */
	{0x800000, 0x808000, 0x900000}, /* FW data RAM 32k */
	{0x840000, 0x860000, 0x908000}, /* peripheral data RAM 128k/96k used */
	{0x880000, 0x88a000, 0x880000}, /* various RGF */
	{0x8c0000, 0x949000, 0x8c0000}, /* trivial mapping for upper area */
	/*
	 * 920000..930000 ucode code RAM
	 * 930000..932000 ucode data RAM
	 * 932000..949000 back-door debug data
	 */
};

/**
 * return AHB address for given firmware/ucode internal (linker) address
 * @x - internal address
 * If address have no valid AHB mapping, return 0
 */
static u32 wmi_addr_remap(u32 x)
{
	uint i;

	for (i = 0; i < ARRAY_SIZE(fw_mapping); i++) {
		if ((x >= fw_mapping[i].from) && (x < fw_mapping[i].to))
			return x + fw_mapping[i].host - fw_mapping[i].from;
	}

	return 0;
}

/**
 * Check address validity for WMI buffer; remap if needed
 * @ptr - internal (linker) fw/ucode address
 *
 * Valid buffer should be DWORD aligned
 *
 * return address for accessing buffer from the host;
 * if buffer is not valid, return NULL.
 */
void __iomem *wmi_buffer(struct wil6210_priv *wil, __le32 ptr_)
{
	u32 off;
	u32 ptr = le32_to_cpu(ptr_);

	if (ptr % 4)
		return NULL;

	ptr = wmi_addr_remap(ptr);
	if (ptr < WIL6210_FW_HOST_OFF)
		return NULL;

	off = HOSTADDR(ptr);
	if (off > WIL6210_MEM_SIZE - 4)
		return NULL;

	return wil->csr + off;
}

/**
 * Check address validity
 */
void __iomem *wmi_addr(struct wil6210_priv *wil, u32 ptr)
{
	u32 off;

	if (ptr % 4)
		return NULL;

	if (ptr < WIL6210_FW_HOST_OFF)
		return NULL;

	off = HOSTADDR(ptr);
	if (off > WIL6210_MEM_SIZE - 4)
		return NULL;

	return wil->csr + off;
}

int wmi_read_hdr(struct wil6210_priv *wil, __le32 ptr,
		 struct wil6210_mbox_hdr *hdr)
{
	void __iomem *src = wmi_buffer(wil, ptr);
	if (!src)
		return -EINVAL;

	wil_memcpy_fromio_32(hdr, src, sizeof(*hdr));

	return 0;
}

static int __wmi_send(struct wil6210_priv *wil, u16 cmdid, void *buf, u16 len)
{
	struct {
		struct wil6210_mbox_hdr hdr;
		struct wil6210_mbox_hdr_wmi wmi;
	} __packed cmd = {
		.hdr = {
			.type = WIL_MBOX_HDR_TYPE_WMI,
			.flags = 0