cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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manage.c (8635B)


      1// SPDX-License-Identifier: GPL-2.0
      2/* Copyright(c) 1999 - 2018 Intel Corporation. */
      3
      4#include "e1000.h"
      5
      6/**
      7 *  e1000_calculate_checksum - Calculate checksum for buffer
      8 *  @buffer: pointer to EEPROM
      9 *  @length: size of EEPROM to calculate a checksum for
     10 *
     11 *  Calculates the checksum for some buffer on a specified length.  The
     12 *  checksum calculated is returned.
     13 **/
     14static u8 e1000_calculate_checksum(u8 *buffer, u32 length)
     15{
     16	u32 i;
     17	u8 sum = 0;
     18
     19	if (!buffer)
     20		return 0;
     21
     22	for (i = 0; i < length; i++)
     23		sum += buffer[i];
     24
     25	return (u8)(0 - sum);
     26}
     27
     28/**
     29 *  e1000_mng_enable_host_if - Checks host interface is enabled
     30 *  @hw: pointer to the HW structure
     31 *
     32 *  Returns 0 upon success, else -E1000_ERR_HOST_INTERFACE_COMMAND
     33 *
     34 *  This function checks whether the HOST IF is enabled for command operation
     35 *  and also checks whether the previous command is completed.  It busy waits
     36 *  in case of previous command is not completed.
     37 **/
     38static s32 e1000_mng_enable_host_if(struct e1000_hw *hw)
     39{
     40	u32 hicr;
     41	u8 i;
     42
     43	if (!hw->mac.arc_subsystem_valid) {
     44		e_dbg("ARC subsystem not valid.\n");
     45		return -E1000_ERR_HOST_INTERFACE_COMMAND;
     46	}
     47
     48	/* Check that the host interface is enabled. */
     49	hicr = er32(HICR);
     50	if (!(hicr & E1000_HICR_EN)) {
     51		e_dbg("E1000_HOST_EN bit disabled.\n");
     52		return -E1000_ERR_HOST_INTERFACE_COMMAND;
     53	}
     54	/* check the previous command is completed */
     55	for (i = 0; i < E1000_MNG_DHCP_COMMAND_TIMEOUT; i++) {
     56		hicr = er32(HICR);
     57		if (!(hicr & E1000_HICR_C))
     58			break;
     59		mdelay(1);
     60	}
     61
     62	if (i == E1000_MNG_DHCP_COMMAND_TIMEOUT) {
     63		e_dbg("Previous command timeout failed.\n");
     64		return -E1000_ERR_HOST_INTERFACE_COMMAND;
     65	}
     66
     67	return 0;
     68}
     69
     70/**
     71 *  e1000e_check_mng_mode_generic - Generic check management mode
     72 *  @hw: pointer to the HW structure
     73 *
     74 *  Reads the firmware semaphore register and returns true (>0) if
     75 *  manageability is enabled, else false (0).
     76 **/
     77bool e1000e_check_mng_mode_generic(struct e1000_hw *hw)
     78{
     79	u32 fwsm = er32(FWSM);
     80
     81	return (fwsm & E1000_FWSM_MODE_MASK) ==
     82	    (E1000_MNG_IAMT_MODE << E1000_FWSM_MODE_SHIFT);
     83}
     84
     85/**
     86 *  e1000e_enable_tx_pkt_filtering - Enable packet filtering on Tx
     87 *  @hw: pointer to the HW structure
     88 *
     89 *  Enables packet filtering on transmit packets if manageability is enabled
     90 *  and host interface is enabled.
     91 **/
     92bool e1000e_enable_tx_pkt_filtering(struct e1000_hw *hw)
     93{
     94	struct e1000_host_mng_dhcp_cookie *hdr = &hw->mng_cookie;
     95	u32 *buffer = (u32 *)&hw->mng_cookie;
     96	u32 offset;
     97	s32 ret_val, hdr_csum, csum;
     98	u8 i, len;
     99
    100	hw->mac.tx_pkt_filtering = true;
    101
    102	/* No manageability, no filtering */
    103	if (!hw->mac.ops.check_mng_mode(hw)) {
    104		hw->mac.tx_pkt_filtering = false;
    105		return hw->mac.tx_pkt_filtering;
    106	}
    107
    108	/* If we can't read from the host interface for whatever
    109	 * reason, disable filtering.
    110	 */
    111	ret_val = e1000_mng_enable_host_if(hw);
    112	if (ret_val) {
    113		hw->mac.tx_pkt_filtering = false;
    114		return hw->mac.tx_pkt_filtering;
    115	}
    116
    117	/* Read in the header.  Length and offset are in dwords. */
    118	len = E1000_MNG_DHCP_COOKIE_LENGTH >> 2;
    119	offset = E1000_MNG_DHCP_COOKIE_OFFSET >> 2;
    120	for (i = 0; i < len; i++)
    121		*(buffer + i) = E1000_READ_REG_ARRAY(hw, E1000_HOST_IF,
    122						     offset + i);
    123	hdr_csum = hdr->checksum;
    124	hdr->checksum = 0;
    125	csum = e1000_calculate_checksum((u8 *)hdr,
    126					E1000_MNG_DHCP_COOKIE_LENGTH);
    127	/* If either the checksums or signature don't match, then
    128	 * the cookie area isn't considered valid, in which case we
    129	 * take the safe route of assuming Tx filtering is enabled.
    130	 */
    131	if ((hdr_csum != csum) || (hdr->signature != E1000_IAMT_SIGNATURE)) {
    132		hw->mac.tx_pkt_filtering = true;
    133		return hw->mac.tx_pkt_filtering;
    134	}
    135
    136	/* Cookie area is valid, make the final check for filtering. */
    137	if (!(hdr->status & E1000_MNG_DHCP_COOKIE_STATUS_PARSING))
    138		hw->mac.tx_pkt_filtering = false;
    139
    140	return hw->mac.tx_pkt_filtering;
    141}
    142
    143/**
    144 *  e1000_mng_write_cmd_header - Writes manageability command header
    145 *  @hw: pointer to the HW structure
    146 *  @hdr: pointer to the host interface command header
    147 *
    148 *  Writes the command header after does the checksum calculation.
    149 **/
    150static s32 e1000_mng_write_cmd_header(struct e1000_hw *hw,
    151				      struct e1000_host_mng_command_header *hdr)
    152{
    153	u16 i, length = sizeof(struct e1000_host_mng_command_header);
    154
    155	/* Write the whole command header structure with new checksum. */
    156
    157	hdr->checksum = e1000_calculate_checksum((u8 *)hdr, length);
    158
    159	length >>= 2;
    160	/* Write the relevant command block into the ram area. */
    161	for (i = 0; i < length; i++) {
    162		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, i, *((u32 *)hdr + i));
    163		e1e_flush();
    164	}
    165
    166	return 0;
    167}
    168
    169/**
    170 *  e1000_mng_host_if_write - Write to the manageability host interface
    171 *  @hw: pointer to the HW structure
    172 *  @buffer: pointer to the host interface buffer
    173 *  @length: size of the buffer
    174 *  @offset: location in the buffer to write to
    175 *  @sum: sum of the data (not checksum)
    176 *
    177 *  This function writes the buffer content at the offset given on the host if.
    178 *  It also does alignment considerations to do the writes in most efficient
    179 *  way.  Also fills up the sum of the buffer in *buffer parameter.
    180 **/
    181static s32 e1000_mng_host_if_write(struct e1000_hw *hw, u8 *buffer,
    182				   u16 length, u16 offset, u8 *sum)
    183{
    184	u8 *tmp;
    185	u8 *bufptr = buffer;
    186	u32 data = 0;
    187	u16 remaining, i, j, prev_bytes;
    188
    189	/* sum = only sum of the data and it is not checksum */
    190
    191	if (length == 0 || offset + length > E1000_HI_MAX_MNG_DATA_LENGTH)
    192		return -E1000_ERR_PARAM;
    193
    194	tmp = (u8 *)&data;
    195	prev_bytes = offset & 0x3;
    196	offset >>= 2;
    197
    198	if (prev_bytes) {
    199		data = E1000_READ_REG_ARRAY(hw, E1000_HOST_IF, offset);
    200		for (j = prev_bytes; j < sizeof(u32); j++) {
    201			*(tmp + j) = *bufptr++;
    202			*sum += *(tmp + j);
    203		}
    204		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset, data);
    205		length -= j - prev_bytes;
    206		offset++;
    207	}
    208
    209	remaining = length & 0x3;
    210	length -= remaining;
    211
    212	/* Calculate length in DWORDs */
    213	length >>= 2;
    214
    215	/* The device driver writes the relevant command block into the
    216	 * ram area.
    217	 */
    218	for (i = 0; i < length; i++) {
    219		for (j = 0; j < sizeof(u32); j++) {
    220			*(tmp + j) = *bufptr++;
    221			*sum += *(tmp + j);
    222		}
    223
    224		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset + i, data);
    225	}
    226	if (remaining) {
    227		for (j = 0; j < sizeof(u32); j++) {
    228			if (j < remaining)
    229				*(tmp + j) = *bufptr++;
    230			else
    231				*(tmp + j) = 0;
    232
    233			*sum += *(tmp + j);
    234		}
    235		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset + i, data);
    236	}
    237
    238	return 0;
    239}
    240
    241/**
    242 *  e1000e_mng_write_dhcp_info - Writes DHCP info to host interface
    243 *  @hw: pointer to the HW structure
    244 *  @buffer: pointer to the host interface
    245 *  @length: size of the buffer
    246 *
    247 *  Writes the DHCP information to the host interface.
    248 **/
    249s32 e1000e_mng_write_dhcp_info(struct e1000_hw *hw, u8 *buffer, u16 length)
    250{
    251	struct e1000_host_mng_command_header hdr;
    252	s32 ret_val;
    253	u32 hicr;
    254
    255	hdr.command_id = E1000_MNG_DHCP_TX_PAYLOAD_CMD;
    256	hdr.command_length = length;
    257	hdr.reserved1 = 0;
    258	hdr.reserved2 = 0;
    259	hdr.checksum = 0;
    260
    261	/* Enable the host interface */
    262	ret_val = e1000_mng_enable_host_if(hw);
    263	if (ret_val)
    264		return ret_val;
    265
    266	/* Populate the host interface with the contents of "buffer". */
    267	ret_val = e1000_mng_host_if_write(hw, buffer, length,
    268					  sizeof(hdr), &(hdr.checksum));
    269	if (ret_val)
    270		return ret_val;
    271
    272	/* Write the manageability command header */
    273	ret_val = e1000_mng_write_cmd_header(hw, &hdr);
    274	if (ret_val)
    275		return ret_val;
    276
    277	/* Tell the ARC a new command is pending. */
    278	hicr = er32(HICR);
    279	ew32(HICR, hicr | E1000_HICR_C);
    280
    281	return 0;
    282}
    283
    284/**
    285 *  e1000e_enable_mng_pass_thru - Check if management passthrough is needed
    286 *  @hw: pointer to the HW structure
    287 *
    288 *  Verifies the hardware needs to leave interface enabled so that frames can
    289 *  be directed to and from the management interface.
    290 **/
    291bool e1000e_enable_mng_pass_thru(struct e1000_hw *hw)
    292{
    293	u32 manc;
    294	u32 fwsm, factps;
    295
    296	manc = er32(MANC);
    297
    298	if (!(manc & E1000_MANC_RCV_TCO_EN))
    299		return false;
    300
    301	if (hw->mac.has_fwsm) {
    302		fwsm = er32(FWSM);
    303		factps = er32(FACTPS);
    304
    305		if (!(factps & E1000_FACTPS_MNGCG) &&
    306		    ((fwsm & E1000_FWSM_MODE_MASK) ==
    307		     (e1000_mng_mode_pt << E1000_FWSM_MODE_SHIFT)))
    308			return true;
    309	} else if ((hw->mac.type == e1000_82574) ||
    310		   (hw->mac.type == e1000_82583)) {
    311		u16 data;
    312		s32 ret_val;
    313
    314		factps = er32(FACTPS);
    315		ret_val = e1000_read_nvm(hw, NVM_INIT_CONTROL2_REG, 1, &data);
    316		if (ret_val)
    317			return false;
    318
    319		if (!(factps & E1000_FACTPS_MNGCG) &&
    320		    ((data & E1000_NVM_INIT_CTRL2_MNGM) ==
    321		     (e1000_mng_mode_pt << 13)))
    322			return true;
    323	} else if ((manc & E1000_MANC_SMBUS_EN) &&
    324		   !(manc & E1000_MANC_ASF_EN)) {
    325		return true;
    326	}
    327
    328	return false;
    329}