linux/drivers/scsi/ufs/cdns-pltfrm.c
Anil Varughese e55f24ffa9 scsi: ufs: Disable local LCC in .link_startup_notify() in Cadence UFS
Some UFS devices have issues if LCC is enabled. So we are setting
PA_LOCAL_TX_LCC_Enable to 0 before link startup which will make sure that
both host and device TX LCC are disabled once link startup is completed.

Signed-off-by: Anil Varughese <aniljoy@cadence.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-08-29 17:42:52 -04:00

229 lines
5.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Platform UFS Host driver for Cadence controller
*
* Copyright (C) 2018 Cadence Design Systems, Inc.
*
* Authors:
* Jan Kotas <jank@cadence.com>
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/time.h>
#include "ufshcd-pltfrm.h"
#define CDNS_UFS_REG_HCLKDIV 0xFC
#define CDNS_UFS_REG_PHY_XCFGD1 0x113C
/**
* Sets HCLKDIV register value based on the core_clk
* @hba: host controller instance
*
* Return zero for success and non-zero for failure
*/
static int cdns_ufs_set_hclkdiv(struct ufs_hba *hba)
{
struct ufs_clk_info *clki;
struct list_head *head = &hba->clk_list_head;
unsigned long core_clk_rate = 0;
u32 core_clk_div = 0;
if (list_empty(head))
return 0;
list_for_each_entry(clki, head, list) {
if (IS_ERR_OR_NULL(clki->clk))
continue;
if (!strcmp(clki->name, "core_clk"))
core_clk_rate = clk_get_rate(clki->clk);
}
if (!core_clk_rate) {
dev_err(hba->dev, "%s: unable to find core_clk rate\n",
__func__);
return -EINVAL;
}
core_clk_div = core_clk_rate / USEC_PER_SEC;
ufshcd_writel(hba, core_clk_div, CDNS_UFS_REG_HCLKDIV);
/**
* Make sure the register was updated,
* UniPro layer will not work with an incorrect value.
*/
mb();
return 0;
}
/**
* Called before and after HCE enable bit is set.
* @hba: host controller instance
* @status: notify stage (pre, post change)
*
* Return zero for success and non-zero for failure
*/
static int cdns_ufs_hce_enable_notify(struct ufs_hba *hba,
enum ufs_notify_change_status status)
{
if (status != PRE_CHANGE)
return 0;
return cdns_ufs_set_hclkdiv(hba);
}
/**
* Called before and after Link startup is carried out.
* @hba: host controller instance
* @status: notify stage (pre, post change)
*
* Return zero for success and non-zero for failure
*/
static int cdns_ufs_link_startup_notify(struct ufs_hba *hba,
enum ufs_notify_change_status status)
{
if (status != PRE_CHANGE)
return 0;
/*
* Some UFS devices have issues if LCC is enabled.
* So we are setting PA_Local_TX_LCC_Enable to 0
* before link startup which will make sure that both host
* and device TX LCC are disabled once link startup is
* completed.
*/
ufshcd_dme_set(hba, UIC_ARG_MIB(PA_LOCAL_TX_LCC_ENABLE), 0);
return 0;
}
/**
* cdns_ufs_init - performs additional ufs initialization
* @hba: host controller instance
*
* Returns status of initialization
*/
static int cdns_ufs_init(struct ufs_hba *hba)
{
int status = 0;
if (hba->vops && hba->vops->phy_initialization)
status = hba->vops->phy_initialization(hba);
return status;
}
/**
* cdns_ufs_m31_16nm_phy_initialization - performs m31 phy initialization
* @hba: host controller instance
*
* Always returns 0
*/
static int cdns_ufs_m31_16nm_phy_initialization(struct ufs_hba *hba)
{
u32 data;
/* Increase RX_Advanced_Min_ActivateTime_Capability */
data = ufshcd_readl(hba, CDNS_UFS_REG_PHY_XCFGD1);
data |= BIT(24);
ufshcd_writel(hba, data, CDNS_UFS_REG_PHY_XCFGD1);
return 0;
}
static const struct ufs_hba_variant_ops cdns_ufs_pltfm_hba_vops = {
.name = "cdns-ufs-pltfm",
.hce_enable_notify = cdns_ufs_hce_enable_notify,
.link_startup_notify = cdns_ufs_link_startup_notify,
};
static const struct ufs_hba_variant_ops cdns_ufs_m31_16nm_pltfm_hba_vops = {
.name = "cdns-ufs-pltfm",
.init = cdns_ufs_init,
.hce_enable_notify = cdns_ufs_hce_enable_notify,
.link_startup_notify = cdns_ufs_link_startup_notify,
.phy_initialization = cdns_ufs_m31_16nm_phy_initialization,
};
static const struct of_device_id cdns_ufs_of_match[] = {
{
.compatible = "cdns,ufshc",
.data = &cdns_ufs_pltfm_hba_vops,
},
{
.compatible = "cdns,ufshc-m31-16nm",
.data = &cdns_ufs_m31_16nm_pltfm_hba_vops,
},
{ },
};
MODULE_DEVICE_TABLE(of, cdns_ufs_of_match);
/**
* cdns_ufs_pltfrm_probe - probe routine of the driver
* @pdev: pointer to platform device handle
*
* Return zero for success and non-zero for failure
*/
static int cdns_ufs_pltfrm_probe(struct platform_device *pdev)
{
int err;
const struct of_device_id *of_id;
struct ufs_hba_variant_ops *vops;
struct device *dev = &pdev->dev;
of_id = of_match_node(cdns_ufs_of_match, dev->of_node);
vops = (struct ufs_hba_variant_ops *)of_id->data;
/* Perform generic probe */
err = ufshcd_pltfrm_init(pdev, vops);
if (err)
dev_err(dev, "ufshcd_pltfrm_init() failed %d\n", err);
return err;
}
/**
* cdns_ufs_pltfrm_remove - removes the ufs driver
* @pdev: pointer to platform device handle
*
* Always returns 0
*/
static int cdns_ufs_pltfrm_remove(struct platform_device *pdev)
{
struct ufs_hba *hba = platform_get_drvdata(pdev);
ufshcd_remove(hba);
return 0;
}
static const struct dev_pm_ops cdns_ufs_dev_pm_ops = {
.suspend = ufshcd_pltfrm_suspend,
.resume = ufshcd_pltfrm_resume,
.runtime_suspend = ufshcd_pltfrm_runtime_suspend,
.runtime_resume = ufshcd_pltfrm_runtime_resume,
.runtime_idle = ufshcd_pltfrm_runtime_idle,
};
static struct platform_driver cdns_ufs_pltfrm_driver = {
.probe = cdns_ufs_pltfrm_probe,
.remove = cdns_ufs_pltfrm_remove,
.driver = {
.name = "cdns-ufshcd",
.pm = &cdns_ufs_dev_pm_ops,
.of_match_table = cdns_ufs_of_match,
},
};
module_platform_driver(cdns_ufs_pltfrm_driver);
MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
MODULE_DESCRIPTION("Cadence UFS host controller platform driver");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(UFSHCD_DRIVER_VERSION);