/*
 * Copyright 2019 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 */
#include <linux/pci.h>

#include "amdgpu.h"
#include "amdgpu_i2c.h"
#include "smu_v11_0_i2c.h"
#include "atom.h"
#include "amdgpu_fru_eeprom.h"
#include "amdgpu_eeprom.h"

#define FRU_EEPROM_MADDR_6      0x60000
#define FRU_EEPROM_MADDR_8      0x80000

static bool is_fru_eeprom_supported(struct amdgpu_device *adev, u32 *fru_addr)
{
	/* Only server cards have the FRU EEPROM
	 * TODO: See if we can figure this out dynamically instead of
	 * having to parse VBIOS versions.
	 */
	struct atom_context *atom_ctx = adev->mode_info.atom_context;

	/* The i2c access is blocked on VF
	 * TODO: Need other way to get the info
	 */
	if (amdgpu_sriov_vf(adev))
		return false;

	/* The default I2C EEPROM address of the FRU.
	 */
	if (fru_addr)
		*fru_addr = FRU_EEPROM_MADDR_8;

	/* VBIOS is of the format ###-DXXXYYYY-##. For SKU identification,
	 * we can use just the "DXXX" portion. If there were more models, we
	 * could convert the 3 characters to a hex integer and use a switch
	 * for ease/speed/readability. For now, 2 string comparisons are
	 * reasonable and not too expensive
	 */
	switch (adev->asic_type) {
	case CHIP_VEGA20:
		/* D161 and D163 are the VG20 server SKUs */
		if (strnstr(atom_ctx->vbios_version, "D161",
			    sizeof(atom_ctx->vbios_version)) ||
		    strnstr(atom_ctx->vbios_version, "D163",
			    sizeof(atom_ctx->vbios_version))) {
			if (fru_addr)
				*fru_addr = FRU_EEPROM_MADDR_6;
			return true;
		} else {
			return false;
		}
	case CHIP_ALDEBARAN:
		/* All Aldebaran SKUs have an FRU */
		if (!strnstr(atom_ctx->vbios_version, "D673",
			     sizeof(atom_ctx->vbios_version)))
			if (fru_addr)
				*fru_addr = FRU_EEPROM_MADDR_6;
		return true;
	case CHIP_SIENNA_CICHLID:
		if (strnstr(atom_ctx->vbios_version, "D603",
			    sizeof(atom_ctx->vbios_version))) {
			if (strnstr(atom_ctx->vbios_version, "D603GLXE",
				    sizeof(atom_ctx->vbios_version))) {
				return false;
			} else {
				if (fru_addr)
					*fru_addr = FRU_EEPROM_MADDR_6;
				return true;
			}
		} else {
			return false;
		}
	default:
		return false;
	}
}

int amdgpu_fru_get_product_info(struct amdgpu_device *adev)
{
	unsigned char buf[8], *pia;
	u32 addr, fru_addr;
	int size, len;
	u8 csum;

	if (!is_fru_eeprom_supported(adev, &fru_addr))
		return 0;

	/* If algo exists, it means that the i2c_adapter's initialized */
	if (!adev->pm.fru_eeprom_i2c_bus || !adev->pm.fru_eeprom_i2c_bus->algo) {
		DRM_WARN("Cannot access FRU, EEPROM accessor not initialized");
		return -ENODEV;
	}

	/* Read the IPMI Common header */
	len = amdgpu_eeprom_read(adev->pm.fru_eeprom_i2c_bus, fru_addr, buf,
				 sizeof(buf));
	if (len != 8) {
		DRM_ERROR("Couldn't read the IPMI Common Header: %d", len);
		return len < 0 ? len : -EIO;
	}

	if (buf[0] != 1) {
		DRM_ERROR("Bad IPMI Common Header version: 0x%02x", buf[0]);
		return -EIO;
	}

	for (csum = 0; len > 0; len--)
		csum += buf[len - 1];
	if (csum) {
		DRM_ERROR("Bad IPMI Common Header checksum: 0x%02x", csum);
		return -EIO;
	}

	/* Get the offset to the Product Info Area (PIA). */
	addr = buf[4] * 8;
	if (!addr)
		return 0;

	/* Get the absolute address to the PIA. */
	addr += fru_addr;

	/* Read the header of the PIA. */
	len = amdgpu_eeprom_read(adev->pm.fru_eeprom_i2c_bus, addr, buf, 3);
	if (len != 3) {
		DRM_ERROR("Couldn't read the Product Info Area header: %d", len);
		return len < 0 ? len : -EIO;
	}

	if (buf[0] != 1) {
		DRM_ERROR("Bad IPMI Product Info Area version: 0x%02x", buf[0]);
		return -EIO;
	}

	size = buf[1] * 8;
	pia = kzalloc(size, GFP_KERNEL);
	if (!pia)
		return -ENOMEM;

	/* Read the whole PIA. */
	len = amdgpu_eeprom_read(adev->pm.fru_eeprom_i2c_bus, addr, pia, size);
	if (len != size) {
		kfree(pia);
		DRM_ERROR("Couldn't read the Product Info Area: %d", len);
		return len < 0 ? len : -EIO;
	}

	for (csum = 0; size > 0; size--)
		csum += pia[size - 1];
	if (csum) {
		DRM_ERROR("Bad Product Info Area checksum: 0x%02x", csum);
		return -EIO;
	}

	/* Now extract useful information from the PIA.
	 *
	 * Skip the Manufacturer Name at [3] and go directly to
	 * the Product Name field.
	 */
	addr = 3 + 1 + (pia[3] & 0x3F);
	if (addr + 1 >= len)
		goto Out;
	memcpy(adev->product_name, pia + addr + 1,
	       min_t(size_t,
		     sizeof(adev->product_name),
		     pia[addr] & 0x3F));
	adev->product_name[sizeof(adev->product_name) - 1] = '\0';

	/* Go to the Product Part/Model Number field. */
	addr += 1 + (pia[addr] & 0x3F);
	if (addr + 1 >= len)
		goto Out;
	memcpy(adev->product_number, pia + addr + 1,
	       min_t(size_t,
		     sizeof(adev->product_number),
		     pia[addr] & 0x3F));
	adev->product_number[sizeof(adev->product_number) - 1] = '\0';

	/* Go to the Product Version field. */
	addr += 1 + (pia[addr] & 0x3F);

	/* Go to the Product Serial Number field. */
	addr += 1 + (pia[addr] & 0x3F);
	if (addr + 1 >= len)
		goto Out;
	memcpy(adev->serial, pia + addr + 1, min_t(size_t,
						   sizeof(adev->serial),
						   pia[addr] & 0x3F));
	adev->serial[sizeof(adev->serial) - 1] = '\0';
Out:
	kfree(pia);
	return 0;
}