Re: [PATCH 2/3] EDAC, altera: Add Arria10 SD-MMC EDAC support

[Borislav Petkov]

On Tue, Aug 02, 2016 at 10:56:20AM -0500, tthayer@xxxxxxxxxxxxxxxxxxxxx wrote:
> From: Thor Thayer <tthayer@xxxxxxxxxxxxxxxxxxxxx>
> 
> Add Altera Arria10 SD-MMC FIFO memory EDAC support. The SD-MMC
> is a dual port RAM implementation which is different than any
> of the other peripherals and therefore requires additional code.
> 
> Signed-off-by: Thor Thayer <tthayer@xxxxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/edac/Kconfig       |    7 ++
>  drivers/edac/altera_edac.c |  188 +++++++++++++++++++++++++++++++++++++++++++-
>  drivers/edac/altera_edac.h |    5 ++
>  3 files changed, 199 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
> index 72752f4..394cd16 100644
> --- a/drivers/edac/Kconfig
> +++ b/drivers/edac/Kconfig
> @@ -426,6 +426,13 @@ config EDAC_ALTERA_QSPI
>  	  Support for error detection and correction on the
>  	  Altera QSPI FIFO Memory for Altera SoCs.
>  
> +config EDAC_ALTERA_SDMMC
> +	bool "Altera SDMMC FIFO ECC"
> +	depends on EDAC_ALTERA=y && MMC_DW
> +	help
> +	  Support for error detection and correction on the
> +	  Altera SDMMC FIFO Memory for Altera SoCs.
> +
>  config EDAC_SYNOPSYS
>  	tristate "Synopsys DDR Memory Controller"
>  	depends on EDAC_MM_EDAC && ARCH_ZYNQ
> diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
> index 28247f8..8b5177e 100644
> --- a/drivers/edac/altera_edac.c
> +++ b/drivers/edac/altera_edac.c
> @@ -1393,6 +1393,188 @@ early_initcall(socfpga_init_qspi_ecc);
>  
>  #endif	/* CONFIG_EDAC_ALTERA_QSPI */
>  
> +/********************* SDMMC Device Functions **********************/
> +
> +#ifdef CONFIG_EDAC_ALTERA_SDMMC
> +
> +static const struct edac_device_prv_data a10_sdmmceccb_data;
> +static int altr_portb_setup(struct altr_edac_device_dev *device)
> +{
> +	struct edac_device_ctl_info *dci;
> +	struct altr_edac_device_dev *altdev;
> +	char *ecc_name = "sdmmcb-ecc";
> +	int edac_idx, rc;
> +	struct device_node *np;
> +	const struct edac_device_prv_data *prv = &a10_sdmmceccb_data;
> +
> +	rc = altr_check_ecc_deps(device);
> +	if (rc)
> +		return rc;
> +
> +	/* Create the PortB EDAC device */
> +	edac_idx = edac_device_alloc_index();
> +	dci = edac_device_alloc_ctl_info(sizeof(*altdev), ecc_name, 1,
> +					 ecc_name, 1, 0, NULL, 0, edac_idx);
> +	if (!dci) {
> +		edac_printk(KERN_ERR, EDAC_DEVICE,
> +			    "%s: Unable to allocate PortB EDAC device\n",
> +			    ecc_name);
> +		return -ENOMEM;
> +	}
> +
> +	/* Initialize the PortB EDAC device structure from PortA structure */
> +	altdev = dci->pvt_info;
> +	*altdev = *device;
> +
> +	if (!devres_open_group(&altdev->ddev, altr_portb_setup, GFP_KERNEL))
> +		return -ENOMEM;
> +
> +	/* Update PortB specific values */
> +	altdev->edac_dev_name = ecc_name;
> +	altdev->edac_idx = edac_idx;
> +	altdev->edac_dev = dci;
> +	altdev->data = prv;
> +	dci->dev = &altdev->ddev;
> +	dci->ctl_name = "Altera ECC Manager";
> +	dci->mod_name = ecc_name;
> +	dci->dev_name = ecc_name;
> +
> +	/* Find the SD/MMC device tree Node then update the IRQs for PortB */
> +	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-sdmmc-ecc");

So why aren't you doing this thing first in the function so that...

> +	if (!np) {
> +		rc = -ENODEV;
> +		goto err_release_group_1;

... you can save yourself the unwind work in err_release_group_1?

In general, make sure you're doing all the work of poking at the
hardware so that you make sure you have the right resources *before* you
go and allocate and init stuff here.

Should make the error paths simpler and the function body smaller.

> +	}
> +
> +	altdev->sb_irq = irq_of_parse_and_map(np, 2);
> +	if (!altdev->sb_irq) {
> +		edac_printk(KERN_ERR, EDAC_DEVICE, "Error PortB SBIRQ alloc\n");
> +		rc = -ENODEV;
> +		goto err_release_group_1;
> +	}
> +	rc = devm_request_irq(&altdev->ddev, altdev->sb_irq,
> +			      prv->ecc_irq_handler,
> +			      IRQF_SHARED, ecc_name, altdev);
> +	if (rc) {
> +		edac_printk(KERN_ERR, EDAC_DEVICE, "PortB SBERR IRQ error\n");
> +		goto err_release_group_1;
> +	}
> +
> +	altdev->db_irq = irq_of_parse_and_map(np, 3);
> +	if (!altdev->db_irq) {
> +		edac_printk(KERN_ERR, EDAC_DEVICE, "Error PortB DBIRQ alloc\n");
> +		rc = -ENODEV;
> +		goto err_release_group_1;
> +	}
> +	rc = devm_request_irq(&altdev->ddev, altdev->db_irq,
> +			      prv->ecc_irq_handler,
> +			      IRQF_SHARED, ecc_name, altdev);
> +	if (rc) {
> +		edac_printk(KERN_ERR, EDAC_DEVICE, "PortB DBERR IRQ error\n");
> +		goto err_release_group_1;
> +	}
> +
> +	rc = edac_device_add_device(dci);
> +	if (rc) {
> +		edac_printk(KERN_ERR, EDAC_DEVICE,
> +			    "edac_device_add_device portB failed\n");
> +		rc = -ENOMEM;
> +		goto err_release_group_1;
> +	}
> +	altr_create_edacdev_dbgfs(dci, prv);
> +
> +	list_add(&altdev->next, &altdev->edac->a10_ecc_devices);
> +
> +	devres_remove_group(&altdev->ddev, altr_portb_setup);
> +
> +	return 0;
> +
> +err_release_group_1:
> +	edac_device_free_ctl_info(dci);
> +	devres_release_group(&altdev->ddev, altr_portb_setup);
> +	edac_printk(KERN_ERR, EDAC_DEVICE,
> +		    "%s:Error setting up EDAC device: %d\n", ecc_name, rc);
> +	return rc;
> +}
> +
> +static irqreturn_t  altr_edac_a10_ecc_irq_portb(int irq, void *dev_id)
> +{
> +	struct altr_edac_device_dev *ad = dev_id;
> +	void __iomem  *base = ad->base;
> +	const struct edac_device_prv_data *priv = ad->data;
> +
> +	if (irq == ad->sb_irq) {
> +		writel(priv->ce_clear_mask,
> +		       base + ALTR_A10_ECC_INTSTAT_OFST);
> +		edac_device_handle_ce(ad->edac_dev, 0, 0, ad->edac_dev_name);
> +		return IRQ_HANDLED;
> +	} else if (irq == ad->db_irq) {
> +		writel(priv->ue_clear_mask,
> +		       base + ALTR_A10_ECC_INTSTAT_OFST);
> +		edac_device_handle_ue(ad->edac_dev, 0, 0, ad->edac_dev_name);
> +		return IRQ_HANDLED;
> +	}
> +
> +	WARN_ON(1);

WARN(1, "Strange IRQ%d on Port B... 

or something like that which is more informative.

> +
> +	return IRQ_NONE;
> +}
> +
> +static const struct edac_device_prv_data a10_sdmmcecca_data = {
> +	.setup = altr_portb_setup,
> +	.ce_clear_mask = ALTR_A10_ECC_SERRPENA,
> +	.ue_clear_mask = ALTR_A10_ECC_DERRPENA,
> +	.dbgfs_name = "altr_trigger",
> +	.ecc_enable_mask = ALTR_A10_COMMON_ECC_EN_CTL,
> +	.ecc_en_ofst = ALTR_A10_ECC_CTRL_OFST,
> +	.ce_set_mask = ALTR_A10_ECC_SERRPENA,
> +	.ue_set_mask = ALTR_A10_ECC_DERRPENA,
> +	.set_err_ofst = ALTR_A10_ECC_INTTEST_OFST,
> +	.ecc_irq_handler = altr_edac_a10_ecc_irq,
> +	.inject_fops = &altr_edac_a10_device_inject_fops,
> +};
> +
> +static const struct edac_device_prv_data a10_sdmmceccb_data = {
> +	.setup = altr_portb_setup,
> +	.ce_clear_mask = ALTR_A10_ECC_SERRPENB,
> +	.ue_clear_mask = ALTR_A10_ECC_DERRPENB,
> +	.dbgfs_name = "altr_trigger",
> +	.ecc_enable_mask = ALTR_A10_COMMON_ECC_EN_CTL,
> +	.ecc_en_ofst = ALTR_A10_ECC_CTRL_OFST,
> +	.ce_set_mask = ALTR_A10_ECC_TSERRB,
> +	.ue_set_mask = ALTR_A10_ECC_TDERRB,
> +	.set_err_ofst = ALTR_A10_ECC_INTTEST_OFST,
> +	.ecc_irq_handler = altr_edac_a10_ecc_irq_portb,
> +	.inject_fops = &altr_edac_a10_device_inject_fops,
> +};
> +
> +static int __init socfpga_init_sdmmc_ecc(void)
> +{
> +	int rc = -ENODEV;
> +	struct device_node *child = of_find_compatible_node(NULL, NULL,
> +						"altr,socfpga-sdmmc-ecc");
> +	if (!child) {
> +		edac_printk(KERN_ERR, EDAC_DEVICE, "SDMMC node not found\n");

Are you sure you want to issue this error each time the driver loads? Is
that even an error condition?

> +		return -ENODEV;
> +	}
> +
> +	if (!of_device_is_available(child))
> +		goto exit;
> +
> +	if (validate_parent_available(child))
> +		goto exit;
> +
> +	rc = altr_init_a10_ecc_block(child, ALTR_A10_SDMMC_IRQ_MASK,
> +				     a10_sdmmcecca_data.ecc_enable_mask, 1);
> +exit:
> +	of_node_put(child);
> +	return rc;
> +}
> +
> +early_initcall(socfpga_init_sdmmc_ecc);
> +
> +#endif	/* CONFIG_EDAC_ALTERA_SDMMC */
> +
>  /********************* Arria10 EDAC Device Functions *************************/
>  static const struct of_device_id altr_edac_a10_device_of_match[] = {
>  #ifdef CONFIG_EDAC_ALTERA_L2C
-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
--