p2sblib.c

Go to the documentation of this file.

/* SPDX-License-Identifier: GPL-2.0-only */
 
#define __SIMPLE_DEVICE__
 
#include <console/console.h>
#include <device/pci.h>
#include <device/pci_ids.h>
#include <intelblocks/p2sb.h>
#include <intelblocks/p2sblib.h>
#include <intelblocks/pcr.h>
#include <soc/pci_devs.h>
 
void p2sb_dev_enable_bar(pci_devfn_t dev, uint64_t bar)
{
        /* Enable PCR Base addresses */
        pci_write_config32(dev, PCI_BASE_ADDRESS_0, (uint32_t)bar);
        pci_write_config32(dev, PCI_BASE_ADDRESS_1, (uint32_t)(bar >> 32));
 
        /* Enable P2SB MSE */
        pci_write_config16(dev, PCI_COMMAND, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
}
 
bool p2sb_dev_is_hidden(pci_devfn_t dev)
{
        const uint16_t pci_vid = pci_read_config16(dev, PCI_VENDOR_ID);
 
        if (pci_vid == 0xffff)
                return true;
        if (pci_vid == PCI_VID_INTEL)
                return false;
        printk(BIOS_ERR, "P2SB PCI_VENDOR_ID is invalid, unknown if hidden\n");
        return true;
}
 
static void p2sb_dev_set_hide_bit(pci_devfn_t dev, int hide)
{
        const uint16_t reg = P2SBC + 1;
        const uint8_t mask = P2SBC_HIDE_BIT;
        uint8_t val;
 
        val = pci_read_config8(dev, reg);
        val &= ~mask;
        if (hide)
                val |= mask;
        pci_write_config8(dev, reg, val);
}
 
void p2sb_dev_unhide(pci_devfn_t dev)
{
        p2sb_dev_set_hide_bit(dev, 0);
 
        if (p2sb_dev_is_hidden(dev))
                die_with_post_code(POST_HW_INIT_FAILURE,
                                "Unable to unhide the P2SB device!\n");
}
 
void p2sb_dev_hide(pci_devfn_t dev)
{
        p2sb_dev_set_hide_bit(dev, 1);
 
        if (!p2sb_dev_is_hidden(dev))
                die_with_post_code(POST_HW_INIT_FAILURE,
                                "Unable to hide the P2SB device!\n");
}
 
static void p2sb_execute_sideband_access(pci_devfn_t dev, uint8_t cmd, uint8_t pid,
                                                uint16_t reg, uint32_t *data)
{
        struct pcr_sbi_msg msg = {
                .pid = pid,
                .offset = reg,
                .opcode = cmd,
                .is_posted = false,
                .fast_byte_enable = 0xF,
                .bar = 0,
                .fid = 0
        };
        uint8_t response;
        int status;
 
        /* Unhide the P2SB device */
        p2sb_dev_unhide(dev);
 
        status = pcr_execute_sideband_msg(dev, &msg, data, &response);
        if (status || response)
                printk(BIOS_ERR, "Fail to execute p2sb sideband access\n");
 
        /* Hide the P2SB device */
        p2sb_dev_hide(dev);
}
 
uint32_t p2sb_dev_sbi_read(pci_devfn_t dev, uint8_t pid, uint16_t reg)
{
        uint32_t val = 0;
        p2sb_execute_sideband_access(dev, PCR_READ, pid, reg, &val);
        return val;
}
 
void p2sb_dev_sbi_write(pci_devfn_t dev, uint8_t pid, uint16_t reg, uint32_t val)
{
        p2sb_execute_sideband_access(dev, PCR_WRITE, pid, reg, &val);
}