src/mainboard/siemens/mc_ehl/mainboard.c

/* SPDX-License-Identifier: GPL-2.0-only */

#include <baseboard/variants.h>
#include <bootstate.h>
#include <console/console.h>
#include <device/device.h>
#include <hwilib.h>
#include <i210.h>
#include <soc/gpio.h>
#include <string.h>
#include <timer.h>
#include <timestamp.h>

#define MAX_PATH_DEPTH		12
#define MAX_NUM_MAPPINGS	10

/** \brief This function can decide if a given MAC address is valid or not.
 *         Currently, addresses filled with 0xff or 0x00 are not valid.
 * @param  mac  Buffer to the MAC address to check
 * @return 0    if address is not valid, otherwise 1
 */
static uint8_t is_mac_adr_valid(uint8_t mac[MAC_ADDR_LEN])
{
	for (size_t i = 0; i < MAC_ADDR_LEN; i++) {
		if (mac[i] != 0x00 && mac[i] != 0xff)
			return 1;
		if (mac[i] != mac[0])
			return 1;
	}
	return 0;
}

/** \brief This function will search for a MAC address which can be assigned
 *         to a MACPHY.
 * @param  dev     pointer to PCI device
 * @param  mac     buffer where to store the MAC address
 * @return cb_err  CB_ERR or CB_SUCCESS
 */
enum cb_err mainboard_get_mac_address(struct device *dev, uint8_t mac[MAC_ADDR_LEN])
{
	struct bus *parent = dev->bus;
	uint8_t buf[16], mapping[16], i = 0, chain_len = 0;

	memset(buf, 0, sizeof(buf));
	memset(mapping, 0, sizeof(mapping));

	/* The first entry in the tree is the device itself. */
	buf[0] = dev->path.pci.devfn;
	chain_len = 1;
	for (i = 1; i < MAX_PATH_DEPTH && parent->dev->bus->subordinate; i++) {
		buf[i] = parent->dev->path.pci.devfn;
		chain_len++;
		parent = parent->dev->bus;
	}
	if (i == MAX_PATH_DEPTH) {
		/* The path is deeper than MAX_PATH_DEPTH devices, error. */
		printk(BIOS_ERR, "Too many bridges for %s\n", dev_path(dev));
		return CB_ERR;
	}
	/*
	 * Now construct the mapping based on the device chain starting from
	 * root bridge device to the device itself.
	 */
	mapping[0] = 1;
	mapping[1] = chain_len;
	for (i = 0; i < chain_len; i++)
		mapping[i + 4] = buf[chain_len - i - 1];

	/* Open main hwinfo block */
	if (hwilib_find_blocks("hwinfo.hex") != CB_SUCCESS)
		return CB_ERR;
	/* Now try to find a valid MAC address in hwinfo for this mapping. */
	for (i = 0; i < MAX_NUM_MAPPINGS; i++) {
		if (hwilib_get_field(XMac1Mapping + i, buf, 16) != 16)
			continue;
		if (memcmp(buf, mapping, chain_len + 4))
			continue;
		/* There is a matching mapping available, get MAC address. */
		if (hwilib_get_field(XMac1 + i, mac, MAC_ADDR_LEN) == MAC_ADDR_LEN) {
			if (is_mac_adr_valid(mac))
				return CB_SUCCESS;
		}
		return CB_ERR;
	}
	/* No MAC address found for */
	return CB_ERR;
}

static void wait_for_legacy_dev(void *unused)
{
	uint32_t legacy_delay, us_since_boot;
	struct stopwatch sw;

	/* Open main hwinfo block. */
	if (hwilib_find_blocks("hwinfo.hex") != CB_SUCCESS)
		return;

	/* Get legacy delay parameter from hwinfo. */
	if (hwilib_get_field(LegacyDelay, (uint8_t *) &legacy_delay,
			      sizeof(legacy_delay)) != sizeof(legacy_delay))
		return;

	us_since_boot = get_us_since_boot();
	/* No need to wait if the time since boot is already long enough.*/
	if (us_since_boot > legacy_delay)
		return;
	stopwatch_init_msecs_expire(&sw, (legacy_delay - us_since_boot) / 1000);
	printk(BIOS_NOTICE, "Wait remaining %d of %d us for legacy devices...",
			legacy_delay - us_since_boot, legacy_delay);
	stopwatch_wait_until_expired(&sw);
	printk(BIOS_NOTICE, "done!\n");
}

static void mainboard_init(void *chip_info)
{
	const struct pad_config *pads;
	size_t num;

	pads = variant_gpio_table(&num);
	gpio_configure_pads(pads, num);
}

struct chip_operations mainboard_ops = {
	.init = mainboard_init,
};

BOOT_STATE_INIT_ENTRY(BS_DEV_ENUMERATE, BS_ON_ENTRY, wait_for_legacy_dev, NULL);