ACK: [SRU][F:linux-bluefield][PATCH v2 1/1] UBUNTU: SAUCE: bluefield_edac: Add SMC support

Kleber Souza kleber.souza at canonical.com
Thu Mar 4 10:19:01 UTC 2021


On 20.02.21 06:42, Shravan Kumar Ramani wrote:
> BugLink: https://bugs.launchpad.net/ubuntu/+source/linux-bluefield/+bug/1916318
> 
> This patch adds secure read/write calls to bluefield_edac. The
> ACPI table entry decides whether the secure calls need to be
> used for accessing the EMI registers.
> 
> Signed-off-by: Shravan Kumar Ramani <shravankr at nvidia.com>

With the same comments as Stefan's:

Acked-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>

> ---
>   drivers/edac/bluefield_edac.c | 175 ++++++++++++++++++++++++++++++++++++++----
>   1 file changed, 158 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/edac/bluefield_edac.c b/drivers/edac/bluefield_edac.c
> index e4736eb..87ffdc1 100644
> --- a/drivers/edac/bluefield_edac.c
> +++ b/drivers/edac/bluefield_edac.c
> @@ -1,8 +1,9 @@
> -// SPDX-License-Identifier: GPL-2.0
> +// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
> +
>   /*
>    * Bluefield-specific EDAC driver.
>    *
> - * Copyright (c) 2019 Mellanox Technologies.
> + * Copyright (c) 2020 NVIDIA Corporation.
>    */
>   
>   #include <linux/acpi.h>
> @@ -12,6 +13,7 @@
>   #include <linux/io.h>
>   #include <linux/module.h>
>   #include <linux/platform_device.h>
> +#include <linux/version.h>
>   
>   #include "edac_module.h"
>   
> @@ -47,6 +49,18 @@
>   #define MLXBF_EDAC_MAX_DIMM_PER_MC	2
>   #define MLXBF_EDAC_ERROR_GRAIN		8
>   
> +#define MLNX_WRITE_REG_32		(0x82000009)
> +#define MLNX_READ_REG_32		(0x8200000A)
> +#define MLNX_WRITE_REG_64		(0x8200000B)
> +#define MLNX_READ_REG_64		(0x8200000C)
> +#define MLNX_SIP_SVC_UID		(0x8200ff01)
> +#define MLNX_SIP_SVC_VERSION		(0x8200ff03)
> +
> +#define SMCCC_ACCESS_VIOLATION		(-4)
> +
> +#define MLNX_EDAC_SVC_REQ_MAJOR 0
> +#define MLNX_EDAC_SVC_MIN_MINOR 3
> +
>   /*
>    * Request MLNX_SIP_GET_DIMM_INFO
>    *
> @@ -72,9 +86,12 @@
>   #define MLXBF_DIMM_INFO__PACKAGE_X GENMASK_ULL(31, 24)
>   
>   struct bluefield_edac_priv {
> +	struct device *dev;
>   	int dimm_ranks[MLXBF_EDAC_MAX_DIMM_PER_MC];
>   	void __iomem *emi_base;
>   	int dimm_per_mc;
> +	bool svc_sreg_support;
> +	uint32_t sreg_tbl_edac;
>   };
>   
>   static u64 smc_call1(u64 smc_op, u64 smc_arg)
> @@ -86,6 +103,73 @@ static u64 smc_call1(u64 smc_op, u64 smc_arg)
>   	return res.a0;
>   }
>   
> +static int secure_readl(void __iomem *addr, uint32_t *result, uint32_t sreg_tbl)
> +{
> +	struct arm_smccc_res res;
> +	int status;
> +
> +	arm_smccc_smc(MLNX_READ_REG_32, sreg_tbl, (uintptr_t) addr,
> +			0, 0, 0, 0, 0, &res);
> +
> +	status = res.a0;
> +
> +	switch (status) {
> +	case SMCCC_RET_NOT_SUPPORTED:
> +	case SMCCC_ACCESS_VIOLATION:
> +		return -1;
> +	default:
> +		*result = (uint32_t)res.a1;
> +		return 0;
> +	}
> +
> +}
> +
> +static int secure_writel(void __iomem *addr, uint32_t data, uint32_t sreg_tbl)
> +{
> +	struct arm_smccc_res res;
> +	int status;
> +
> +	arm_smccc_smc(MLNX_WRITE_REG_32, sreg_tbl, data, (uintptr_t) addr,
> +			0, 0, 0, 0, &res);
> +
> +	status = res.a0;
> +
> +	switch (status) {
> +	case SMCCC_RET_NOT_SUPPORTED:
> +	case SMCCC_ACCESS_VIOLATION:
> +		return -1;
> +	default:
> +		return 0;
> +	}
> +
> +}
> +
> +static int edac_readl(void __iomem *addr, uint32_t *result,
> +		      bool sreg_support, uint32_t sreg_tbl)
> +{
> +	int err = 0;
> +
> +	if (sreg_support)
> +		err = secure_readl(addr, result, sreg_tbl);
> +	else
> +		*result = readl(addr);
> +
> +	return err;
> +}
> +
> +static int edac_writel(void __iomem *addr, uint32_t data,
> +		       bool sreg_support, uint32_t sreg_tbl)
> +{
> +	int err = 0;
> +
> +	if (sreg_support)
> +		err = secure_writel(addr, data, sreg_tbl);
> +	else
> +		writel(data, addr);
> +
> +	return err;
> +}
> +
>   /*
>    * Gather the ECC information from the External Memory Interface registers
>    * and report it to the edac handler.
> @@ -99,7 +183,7 @@ static void bluefield_gather_report_ecc(struct mem_ctl_info *mci,
>   	u32 ecc_latch_select, dram_syndrom, serr, derr, syndrom;
>   	enum hw_event_mc_err_type ecc_type;
>   	u64 ecc_dimm_addr;
> -	int ecc_dimm;
> +	int ecc_dimm, err;
>   
>   	ecc_type = is_single_ecc ? HW_EVENT_ERR_CORRECTED :
>   				   HW_EVENT_ERR_UNCORRECTED;
> @@ -109,14 +193,22 @@ static void bluefield_gather_report_ecc(struct mem_ctl_info *mci,
>   	 * registers with information about the last ECC error occurrence.
>   	 */
>   	ecc_latch_select = MLXBF_ECC_LATCH_SEL__START;
> -	writel(ecc_latch_select, priv->emi_base + MLXBF_ECC_LATCH_SEL);
> +	err = edac_writel(priv->emi_base + MLXBF_ECC_LATCH_SEL,
> +			  ecc_latch_select, priv->svc_sreg_support,
> +			  priv->sreg_tbl_edac);
> +	if (err)
> +		dev_err(priv->dev, "ECC latch select write failed.\n");
>   
>   	/*
>   	 * Verify that the ECC reported info in the registers is of the
>   	 * same type as the one asked to report. If not, just report the
>   	 * error without the detailed information.
>   	 */
> -	dram_syndrom = readl(priv->emi_base + MLXBF_SYNDROM);
> +	err = edac_readl(priv->emi_base + MLXBF_SYNDROM, &dram_syndrom,
> +			 priv->svc_sreg_support, priv->sreg_tbl_edac);
> +	if (err)
> +		dev_err(priv->dev, "DRAM syndrom read failed.\n");
> +
>   	serr = FIELD_GET(MLXBF_SYNDROM__SERR, dram_syndrom);
>   	derr = FIELD_GET(MLXBF_SYNDROM__DERR, dram_syndrom);
>   	syndrom = FIELD_GET(MLXBF_SYNDROM__SYN, dram_syndrom);
> @@ -127,13 +219,24 @@ static void bluefield_gather_report_ecc(struct mem_ctl_info *mci,
>   		return;
>   	}
>   
> -	dram_additional_info = readl(priv->emi_base + MLXBF_ADD_INFO);
> +	err = edac_readl(priv->emi_base + MLXBF_ADD_INFO, &dram_additional_info,
> +			 priv->svc_sreg_support, priv->sreg_tbl_edac);
> +	if (err)
> +		dev_err(priv->dev, "DRAM additional info read failed.\n");
> +
>   	err_prank = FIELD_GET(MLXBF_ADD_INFO__ERR_PRANK, dram_additional_info);
>   
>   	ecc_dimm = (err_prank >= 2 && priv->dimm_ranks[0] <= 2) ? 1 : 0;
>   
> -	edea0 = readl(priv->emi_base + MLXBF_ERR_ADDR_0);
> -	edea1 = readl(priv->emi_base + MLXBF_ERR_ADDR_1);
> +	err = edac_readl(priv->emi_base + MLXBF_ERR_ADDR_0, &edea0,
> +			 priv->svc_sreg_support, priv->sreg_tbl_edac);
> +	if (err)
> +		dev_err(priv->dev, "Error addr 0 read failed.\n");
> +
> +	err = edac_readl(priv->emi_base + MLXBF_ERR_ADDR_1, &edea1,
> +			 priv->svc_sreg_support, priv->sreg_tbl_edac);
> +	if (err)
> +		dev_err(priv->dev, "Error addr 1 read failed.\n");
>   
>   	ecc_dimm_addr = ((u64)edea1 << 32) | edea0;
>   
> @@ -147,6 +250,7 @@ static void bluefield_edac_check(struct mem_ctl_info *mci)
>   {
>   	struct bluefield_edac_priv *priv = mci->pvt_info;
>   	u32 ecc_count, single_error_count, double_error_count, ecc_error = 0;
> +	int err;
>   
>   	/*
>   	 * The memory controller might not be initialized by the firmware
> @@ -155,7 +259,11 @@ static void bluefield_edac_check(struct mem_ctl_info *mci)
>   	if (mci->edac_cap == EDAC_FLAG_NONE)
>   		return;
>   
> -	ecc_count = readl(priv->emi_base + MLXBF_ECC_CNT);
> +	err = edac_readl(priv->emi_base + MLXBF_ECC_CNT, &ecc_count,
> +			 priv->svc_sreg_support, priv->sreg_tbl_edac);
> +	if (err)
> +		dev_err(priv->dev, "ECC count read failed.\n");
> +
>   	single_error_count = FIELD_GET(MLXBF_ECC_CNT__SERR_CNT, ecc_count);
>   	double_error_count = FIELD_GET(MLXBF_ECC_CNT__DERR_CNT, ecc_count);
>   
> @@ -172,8 +280,12 @@ static void bluefield_edac_check(struct mem_ctl_info *mci)
>   	}
>   
>   	/* Write to clear reported errors. */
> -	if (ecc_count)
> -		writel(ecc_error, priv->emi_base + MLXBF_ECC_ERR);
> +	if (ecc_count) {
> +		err = edac_writel(priv->emi_base + MLXBF_ECC_ERR, ecc_error,
> +				  priv->svc_sreg_support, priv->sreg_tbl_edac);
> +		if (err)
> +			dev_err(priv->dev, "ECC Error write failed.\n");
> +	}
>   }
>   
>   /* Initialize the DIMMs information for the given memory controller. */
> @@ -244,6 +356,7 @@ static int bluefield_edac_mc_probe(struct platform_device *pdev)
>   	struct bluefield_edac_priv *priv;
>   	struct device *dev = &pdev->dev;
>   	struct edac_mc_layer layers[1];
> +	struct arm_smccc_res res;
>   	struct mem_ctl_info *mci;
>   	struct resource *emi_res;
>   	unsigned int mc_idx, dimm_count;
> @@ -280,12 +393,40 @@ static int bluefield_edac_mc_probe(struct platform_device *pdev)
>   
>   	priv = mci->pvt_info;
>   
> +	/*
> +	 * ACPI indicates whether we use SMCs to access registers or not.
> +	 * If sreg_tbl_perf is not present, just assume we're not using SMCs.
> +	 */
> +	if (device_property_read_u32(dev,
> +				"sec_reg_block", &priv->sreg_tbl_edac)) {
> +		priv->svc_sreg_support = false;
> +	} else {
> +		/*
> +		 * Check service version to see if we actually do support the
> +		 * needed SMCs. If we have the calls we need, mark support for
> +		 * them in the pmc struct.
> +		 */
> +		arm_smccc_smc(MLNX_SIP_SVC_VERSION, 0, 0, 0, 0, 0, 0, 0, &res);
> +		if (res.a0 == MLNX_EDAC_SVC_REQ_MAJOR &&
> +			res.a1 >= MLNX_EDAC_SVC_MIN_MINOR)
> +			priv->svc_sreg_support = true;
> +		else {
> +			dev_err(dev, "Required SMCs are not supported.\n");
> +			ret = -EINVAL;
> +			goto err;
> +		}
> +	}
> +
>   	priv->dimm_per_mc = dimm_count;
> -	priv->emi_base = devm_ioremap_resource(dev, emi_res);
> -	if (IS_ERR(priv->emi_base)) {
> -		dev_err(dev, "failed to map EMI IO resource\n");
> -		ret = PTR_ERR(priv->emi_base);
> -		goto err;
> +	if (!priv->svc_sreg_support) {
> +		priv->emi_base = devm_ioremap_resource(dev, emi_res);
> +		if (IS_ERR(priv->emi_base)) {
> +			dev_err(dev, "failed to map EMI IO resource\n");
> +			ret = PTR_ERR(priv->emi_base);
> +			goto err;
> +		}
> +	} else {
> +		priv->emi_base = (void __iomem *) emi_res->start;
>   	}
>   
>   	mci->pdev = dev;
> @@ -353,4 +494,4 @@ module_platform_driver(bluefield_edac_mc_driver);
>   
>   MODULE_DESCRIPTION("Mellanox BlueField memory edac driver");
>   MODULE_AUTHOR("Mellanox Technologies");
> -MODULE_LICENSE("GPL v2");
> +MODULE_LICENSE("Dual BSD/GPL");
> 




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