Re: [PATCH v1 3/4] drivers: edac: Add EDAC driver support for QCOM SoCs
From: vnkgutta
Date: Fri Aug 10 2018 - 19:03:39 EST
On 2018-08-09 20:59, Borislav Petkov wrote:
On Wed, Aug 01, 2018 at 01:33:34PM -0700, Venkata Narendra Kumar Gutta
wrote:
From: Channagoud Kadabi <ckadabi@xxxxxxxxxxxxxx>
Add error reporting driver for SBEs and DBEs. As of now, this driver
Please write out those abbreviations.
Done, I just followed the other commits which has the same and thought
they are understood in the community,
I'll update it in the next patch set.
supports erp for Last Level Cache Controller (LLCC). This driver takes
care of dumping registers and adding config options to enable and
disable panic when the errors happen in cache.
Co-developed-by: Venkata Narendra Kumar Gutta
<vnkgutta@xxxxxxxxxxxxxx>
Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@xxxxxxxxxxxxxx>
Signed-off-by: Channagoud Kadabi <ckadabi@xxxxxxxxxxxxxx>
The proper order is:
SOB: Author
SOB: Sender/handler/...
So:
Signed-off-by: Channagoud Kadabi <ckadabi@xxxxxxxxxxxxxx>
Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@xxxxxxxxxxxxxx>
Ok, I'll update accordingly.
---
MAINTAINERS | 7 +
drivers/edac/Kconfig | 28 +++
drivers/edac/Makefile | 1 +
drivers/edac/qcom_edac.c | 507
+++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 543 insertions(+)
create mode 100644 drivers/edac/qcom_edac.c
diff --git a/MAINTAINERS b/MAINTAINERS
index f6a9b08..68b3484 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5227,6 +5227,13 @@ L: linux-edac@xxxxxxxxxxxxxxx
S: Maintained
F: drivers/edac/ti_edac.c
+EDAC-QUALCOMM
+M: Channagoud Kadabi<ckadabi@xxxxxxxxxxxxxx>
+M: Venkata Narendra Kumar Gutta<vnkgutta@xxxxxxxxxxxxxx>
Space between name and email address.
+L: linux-arm-msm@xxxxxxxxxxxxxxx
Also
L: linux-edac@xxxxxxxxxxxxxxx
so that the EDAC ML gets CCed too.
Ok, Done
+S: Maintained
+F: drivers/edac/qcom_edac.c
+
EDIROL UA-101/UA-1000 DRIVER
M: Clemens Ladisch <clemens@xxxxxxxxxx>
L: alsa-devel@xxxxxxxxxxxxxxxx (moderated for non-subscribers)
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 57304b2..c654b0e 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -460,4 +460,32 @@ config EDAC_TI
Support for error detection and correction on the
TI SoCs.
+config EDAC_QCOM
+ depends on EDAC=y
Why on EDAC=y? Did you blindly copy it or is there a reason why
edac_core should be only built-in or can it be a module too?
I took it from EDAC_ALTERA example. I want to put it like EDAC_QCOM
should be dependent on EDAC. Doesn't it make any sense or we don't need
this at all?
or do you think it's redundant?
+ tristate "QCOM EDAC Controller"
+ help
+ Support for error detection and correction on the
+ QCOM SoCs.
+
+config EDAC_QCOM_LLCC
+ depends on EDAC_QCOM=y && QCOM_LLCC
+ tristate "QCOM EDAC Controller for LLCC Cache"
+ help
+ Support for error detection and correction on the
+ QCOM LLCC cache. Report errors caught by LLCC ECC
+ mechanism.
+
+ For debugging issues having to do with stability and overall system
+ health, you should probably say 'Y' here.
+
+config EDAC_QCOM_LLCC_PANIC_ON_UE
+ depends on EDAC_QCOM_LLCC
+ bool "Panic on uncorrectable errors - qcom llcc"
+ help
+ Forcibly cause a kernel panic if an uncorrectable error (UE) is
+ detected. This can reduce debugging times on hardware which may be
+ operating at voltages or frequencies outside normal specification.
+
+ For production builds, you should probably say 'N' here.
+
endif # EDAC
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 02b43a7..716096d 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -77,3 +77,4 @@ obj-$(CONFIG_EDAC_ALTERA) += altera_edac.o
obj-$(CONFIG_EDAC_SYNOPSYS) += synopsys_edac.o
obj-$(CONFIG_EDAC_XGENE) += xgene_edac.o
obj-$(CONFIG_EDAC_TI) += ti_edac.o
+obj-$(CONFIG_EDAC_QCOM) += qcom_edac.o
diff --git a/drivers/edac/qcom_edac.c b/drivers/edac/qcom_edac.c
new file mode 100644
index 0000000..cf3e2b0
--- /dev/null
+++ b/drivers/edac/qcom_edac.c
@@ -0,0 +1,507 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/edac.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/smp.h>
+#include <linux/regmap.h>
+#include <linux/interrupt.h>
+#include <linux/soc/qcom/llcc-qcom.h>
+#include "edac_mc.h"
+#include "edac_device.h"
+
+#ifdef CONFIG_EDAC_QCOM_LLCC_PANIC_ON_UE
+#define LLCC_ERP_PANIC_ON_UE 1
+#else
+#define LLCC_ERP_PANIC_ON_UE 0
+#endif
+
+#define EDAC_LLCC "qcom_llcc"
+
+#define TRP_SYN_REG_CNT 6
+
+#define DRP_SYN_REG_CNT 8
+
+#define LLCC_COMMON_STATUS0 0x0003000C
+#define LLCC_LB_CNT_MASK GENMASK(31, 28)
+#define LLCC_LB_CNT_SHIFT 28
+
+/* single & Double Bit syndrome register offsets */
+#define TRP_ECC_SB_ERR_SYN0 0x0002304C
+#define TRP_ECC_DB_ERR_SYN0 0x00020370
+#define DRP_ECC_SB_ERR_SYN0 0x0004204C
+#define DRP_ECC_DB_ERR_SYN0 0x00042070
+
+/* Error register offsets */
+#define TRP_ECC_ERROR_STATUS1 0x00020348
+#define TRP_ECC_ERROR_STATUS0 0x00020344
+#define DRP_ECC_ERROR_STATUS1 0x00042048
+#define DRP_ECC_ERROR_STATUS0 0x00042044
+
+/* TRP, DRP interrupt register offsets */
+#define DRP_INTERRUPT_STATUS 0x00041000
+#define TRP_INTERRUPT_0_STATUS 0x00020480
+#define DRP_INTERRUPT_CLEAR 0x00041008
+#define DRP_ECC_ERROR_CNTR_CLEAR 0x00040004
+#define TRP_INTERRUPT_0_CLEAR 0x00020484
+#define TRP_ECC_ERROR_CNTR_CLEAR 0x00020440
+
+/* Mask and shift macros */
+#define ECC_DB_ERR_COUNT_MASK GENMASK(4, 0)
+#define ECC_DB_ERR_WAYS_MASK GENMASK(31, 16)
+#define ECC_DB_ERR_WAYS_SHIFT BIT(4)
+
+#define ECC_SB_ERR_COUNT_MASK GENMASK(23, 16)
+#define ECC_SB_ERR_COUNT_SHIFT BIT(4)
+#define ECC_SB_ERR_WAYS_MASK GENMASK(15, 0)
+
+#define SB_ECC_ERROR BIT(0)
+#define DB_ECC_ERROR BIT(1)
+
+#define DRP_TRP_INT_CLEAR GENMASK(1, 0)
+#define DRP_TRP_CNT_CLEAR GENMASK(1, 0)
+
+/* Config registers offsets*/
+#define DRP_ECC_ERROR_CFG 0x00040000
+
+/* TRP, DRP interrupt register offsets */
+#define CMN_INTERRUPT_0_ENABLE 0x0003001C
+#define CMN_INTERRUPT_2_ENABLE 0x0003003C
+#define TRP_INTERRUPT_0_ENABLE 0x00020488
+#define DRP_INTERRUPT_ENABLE 0x0004100C
+
+#define SB_ERROR_THRESHOLD 0x1
+#define SB_ERROR_THRESHOLD_SHIFT 24
+#define SB_DB_TRP_INTERRUPT_ENABLE 0x3
+#define TRP0_INTERRUPT_ENABLE 0x1
+#define DRP0_INTERRUPT_ENABLE BIT(6)
+#define SB_DB_DRP_INTERRUPT_ENABLE 0x3
+
+
+enum {
+ LLCC_DRAM_CE = 0,
+ LLCC_DRAM_UE,
+ LLCC_TRAM_CE,
+ LLCC_TRAM_UE,
+};
+
+struct errors_edac {
+ const char *msg;
+ void (*func)(struct edac_device_ctl_info *edev_ctl,
+ int inst_nr, int block_nr, const char *msg);
+};
+
+static const struct errors_edac errors[] = {
+ {"LLCC Data RAM correctable Error", edac_device_handle_ce},
+ {"LLCC Data RAM uncorrectable Error", edac_device_handle_ue},
+ {"LLCC Tag RAM correctable Error", edac_device_handle_ce},
+ {"LLCC Tag RAM uncorrectable Error", edac_device_handle_ue},
+};
An array of function pointers just for two functions?! This looks
silly.
Just do a simple if-else.
Ok, I'll check and update this one.
+
+static int qcom_llcc_core_setup(struct regmap *llcc_bcast_regmap)
+{
+ u32 sb_err_threshold;
+ int ret;
+
+ /* Enable TRP in instance 2 of common interrupt enable register */
+ ret = regmap_update_bits(llcc_bcast_regmap, CMN_INTERRUPT_2_ENABLE,
+ TRP0_INTERRUPT_ENABLE,
+ TRP0_INTERRUPT_ENABLE);
+ if (ret)
+ return ret;
+
+ /* Enable ECC interrupts on Tag Ram */
+ ret = regmap_update_bits(llcc_bcast_regmap, TRP_INTERRUPT_0_ENABLE,
+ SB_DB_TRP_INTERRUPT_ENABLE,
+ SB_DB_TRP_INTERRUPT_ENABLE);
+ if (ret)
+ return ret;
+
+ /* Enable SB error for Data RAM */
+ sb_err_threshold = (SB_ERROR_THRESHOLD << SB_ERROR_THRESHOLD_SHIFT);
+ ret = regmap_write(llcc_bcast_regmap, DRP_ECC_ERROR_CFG,
+ sb_err_threshold);
+ if (ret)
+ return ret;
+
+ /* Enable DRP in instance 2 of common interrupt enable register */
+ ret = regmap_update_bits(llcc_bcast_regmap, CMN_INTERRUPT_2_ENABLE,
+ DRP0_INTERRUPT_ENABLE,
+ DRP0_INTERRUPT_ENABLE);
+ if (ret)
+ return ret;
+
+ /* Enable ECC interrupts on Data Ram */
+ ret = regmap_write(llcc_bcast_regmap, DRP_INTERRUPT_ENABLE,
+ SB_DB_DRP_INTERRUPT_ENABLE);
+ return ret;
+}
+
+/* Clear the error interrupt and counter registers */
+static int qcom_llcc_clear_errors(int err_type, struct llcc_drv_data
*drv)
+{
+ int ret = 0;
+
+ switch (err_type) {
+ case LLCC_DRAM_CE:
+ case LLCC_DRAM_UE:
+ /* Clear the interrupt */
+ ret = regmap_write(drv->bcast_regmap, DRP_INTERRUPT_CLEAR,
+ DRP_TRP_INT_CLEAR);
+ if (ret)
+ return ret;
+
+ /* Clear the counters */
+ ret = regmap_write(drv->bcast_regmap, DRP_ECC_ERROR_CNTR_CLEAR,
+ DRP_TRP_CNT_CLEAR);
+ if (ret)
+ return ret;
+ break;
+ case LLCC_TRAM_CE:
+ case LLCC_TRAM_UE:
+ ret = regmap_write(drv->bcast_regmap, TRP_INTERRUPT_0_CLEAR,
+ DRP_TRP_INT_CLEAR);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(drv->bcast_regmap, TRP_ECC_ERROR_CNTR_CLEAR,
+ DRP_TRP_CNT_CLEAR);
+ if (ret)
+ return ret;
+ break;
+ }
+ return ret;
+}
+
+/* Dump syndrome registers for tag Ram Double bit errors */
+static int dump_trp_db_syn_reg(struct llcc_drv_data *drv, u32 bank)
+{
+ int db_err_cnt, db_err_ways, ret, i;
+ u32 synd_reg, synd_val;
+
+ for (i = 0; i < TRP_SYN_REG_CNT; i++) {
+ synd_reg = TRP_ECC_DB_ERR_SYN0 + (i * 4);
+ ret = regmap_read(drv->regmap, drv->offsets[bank] + synd_reg,
+ &synd_val);
+ if (ret)
+ return ret;
+ edac_printk(KERN_CRIT, EDAC_LLCC, "TRP_ECC_SYN%d: 0x%8x\n",
+ i, synd_val);
+ }
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + TRP_ECC_ERROR_STATUS1,
+ &db_err_cnt);
+ if (ret)
+ return ret;
+ db_err_cnt = (db_err_cnt & ECC_DB_ERR_COUNT_MASK);
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Double-Bit error count: 0x%4x\n",
+ db_err_cnt);
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + TRP_ECC_ERROR_STATUS0,
+ &db_err_ways);
+ if (ret)
+ return ret;
+ db_err_ways = (db_err_ways & ECC_DB_ERR_WAYS_MASK);
+ db_err_ways >>= ECC_DB_ERR_WAYS_SHIFT;
+
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Double-Bit error ways: 0x%4x\n",
+ db_err_ways);
+
+ return ret;
+}
+
+/* Dump syndrome register for tag Ram Single Bit Errors */
+static int dump_trp_sb_syn_reg(struct llcc_drv_data *drv, u32 bank)
+{
+ int sb_err_cnt, sb_err_ways, ret, i;
+ u32 synd_reg, synd_val;
+
+ for (i = 0; i < TRP_SYN_REG_CNT; i++) {
+ synd_reg = TRP_ECC_SB_ERR_SYN0 + (i * 4);
+ ret = regmap_read(drv->regmap, drv->offsets[bank] + synd_reg,
+ &synd_val);
+ if (ret)
+ return ret;
+ edac_printk(KERN_CRIT, EDAC_LLCC, "TRP_ECC_SYN%d: 0x%8x\n", i,
+ synd_val);
+ }
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + TRP_ECC_ERROR_STATUS1,
+ &sb_err_cnt);
+ if (ret)
+ return ret;
+ sb_err_cnt = (sb_err_cnt & ECC_SB_ERR_COUNT_MASK);
+ sb_err_cnt >>= ECC_SB_ERR_COUNT_SHIFT;
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Single-Bit error count: 0x%4x\n",
+ sb_err_cnt);
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + TRP_ECC_ERROR_STATUS0,
+ &sb_err_ways);
+ if (ret)
+ return ret;
+
+ sb_err_ways = sb_err_ways & ECC_SB_ERR_WAYS_MASK;
+
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Single-Bit error ways: 0x%4x\n",
+ sb_err_ways);
+
+ return ret;
+}
+
+/* Dump syndrome registers for Data Ram Double bit errors */
+static int dump_drp_db_syn_reg(struct llcc_drv_data *drv, u32 bank)
+{
+ int db_err_cnt, db_err_ways, ret, i;
+ u32 synd_reg, synd_val;
+
+ for (i = 0; i < DRP_SYN_REG_CNT; i++) {
+ synd_reg = DRP_ECC_DB_ERR_SYN0 + (i * 4);
+ ret = regmap_read(drv->regmap, drv->offsets[bank] + synd_reg,
+ &synd_val);
+ if (ret)
+ return ret;
+ edac_printk(KERN_CRIT, EDAC_LLCC, "DRP_ECC_SYN%d: 0x%8x\n", i,
+ synd_val);
+ }
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + DRP_ECC_ERROR_STATUS1,
+ &db_err_cnt);
+ if (ret)
+ return ret;
+ db_err_cnt = (db_err_cnt & ECC_DB_ERR_COUNT_MASK);
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Double-Bit error count: 0x%4x\n",
+ db_err_cnt);
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + DRP_ECC_ERROR_STATUS0,
+ &db_err_ways);
+ if (ret)
+ return ret;
+ db_err_ways &= ECC_DB_ERR_WAYS_MASK;
+ db_err_ways >>= ECC_DB_ERR_WAYS_SHIFT;
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Double-Bit error ways: 0x%4x\n",
+ db_err_ways);
+
+ return ret;
+}
+
+/* Dump Syndrome registers for Data Ram Single bit errors*/
+static int dump_drp_sb_syn_reg(struct llcc_drv_data *drv, u32 bank)
+{
+ int sb_err_cnt, sb_err_ways, ret, i;
+ u32 synd_reg, synd_val;
+
+ for (i = 0; i < DRP_SYN_REG_CNT; i++) {
+ synd_reg = DRP_ECC_SB_ERR_SYN0 + (i * 4);
+ ret = regmap_read(drv->regmap, drv->offsets[bank] + synd_reg,
+ &synd_val);
+ if (ret)
+ return ret;
+ edac_printk(KERN_CRIT, EDAC_LLCC, "DRP_ECC_SYN%d: 0x%8x\n", i,
+ synd_val);
+ }
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + DRP_ECC_ERROR_STATUS1,
+ &sb_err_cnt);
+ if (ret)
+ return ret;
+ sb_err_cnt &= ECC_SB_ERR_COUNT_MASK;
+ sb_err_cnt >>= ECC_SB_ERR_COUNT_SHIFT;
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Single-Bit error count: 0x%4x\n",
+ sb_err_cnt);
+
+ ret = regmap_read(drv->regmap,
+ drv->offsets[bank] + DRP_ECC_ERROR_STATUS0,
+ &sb_err_ways);
+ if (ret)
+ return ret;
+ sb_err_ways = sb_err_ways & ECC_SB_ERR_WAYS_MASK;
+
+ edac_printk(KERN_CRIT, EDAC_LLCC, "Single-Bit error ways: 0x%4x\n",
+ sb_err_ways);
+
+ return ret;
+}
+
+static int dump_syn_reg(struct edac_device_ctl_info *edev_ctl,
+ int err_type, u32 bank)
+{
+ struct llcc_drv_data *drv = edev_ctl->pvt_info;
+ int ret = 0;
+
+ switch (err_type) {
+ case LLCC_DRAM_CE:
+ ret = dump_drp_sb_syn_reg(drv, bank);
+ break;
+ case LLCC_DRAM_UE:
+ ret = dump_drp_db_syn_reg(drv, bank);
+ break;
+ case LLCC_TRAM_CE:
+ ret = dump_trp_sb_syn_reg(drv, bank);
+ break;
+ case LLCC_TRAM_UE:
+ ret = dump_trp_db_syn_reg(drv, bank);
So those functions look very similar to one another and thus are
quadrupled object code. You could have one function instead and pass
in the register as an arg. Or some other smarter scheme to save object
size...
There are actually 6 different registers foe each case handled in each
function, that's why we had to have different functions with the same
outline. I can explore the way of having a single method and categorize
based on
the error type. But I don't think I will be reducing a lot of object
code. Let me
explore on what can I do on this.
+ break;
+ }
+ if (ret)
+ return ret;
+
+ ret = qcom_llcc_clear_errors(err_type, drv);
+ if (ret)
+ return ret;
+
+ errors[err_type].func(edev_ctl, 0, bank, errors[err_type].msg);
+
+ return ret;
+}
+
+static irqreturn_t
+llcc_ecc_irq_handler (int irq, void *edev_ctl)
Stray " " after function name.
I'll correct this.
+{
+ struct edac_device_ctl_info *edac_dev_ctl;
+ irqreturn_t irq_rc = IRQ_NONE;
+ u32 drp_error, trp_error, i;
+ struct llcc_drv_data *drv;
+ int ret;
+
+ edac_dev_ctl = (struct edac_device_ctl_info *)edev_ctl;
+ drv = edac_dev_ctl->pvt_info;
+
+ for (i = 0; i < drv->num_banks; i++) {
+ /* Look for Data RAM errors */
+ ret = regmap_read(drv->regmap,
+ drv->offsets[i] + DRP_INTERRUPT_STATUS,
+ &drp_error);
+ if (ret)
+ return irq_rc;
+
+ if (drp_error & SB_ECC_ERROR) {
+ edac_printk(KERN_CRIT, EDAC_LLCC,
+ "Single Bit Error detected in Data Ram\n");
+ dump_syn_reg(edev_ctl, LLCC_DRAM_CE, i);
+ irq_rc = IRQ_HANDLED;
+ } else if (drp_error & DB_ECC_ERROR) {
+ edac_printk(KERN_CRIT, EDAC_LLCC,
+ "Double Bit Error detected in Data Ram\n");
+ dump_syn_reg(edev_ctl, LLCC_DRAM_UE, i);
+ irq_rc = IRQ_HANDLED;
+ }
+
+ /* Look for Tag RAM errors */
+ ret = regmap_read(drv->regmap,
+ drv->offsets[i] + TRP_INTERRUPT_0_STATUS,
+ &trp_error);
+ if (ret)
+ return irq_rc;
+ if (trp_error & SB_ECC_ERROR) {
+ edac_printk(KERN_CRIT, EDAC_LLCC,
+ "Single Bit Error detected in Tag Ram\n");
+ dump_syn_reg(edev_ctl, LLCC_TRAM_CE, i);
+ irq_rc = IRQ_HANDLED;
+ } else if (trp_error & DB_ECC_ERROR) {
+ edac_printk(KERN_CRIT, EDAC_LLCC,
+ "Double Bit Error detected in Tag Ram\n");
+ dump_syn_reg(edev_ctl, LLCC_TRAM_UE, i);
+ irq_rc = IRQ_HANDLED;
+ }
+ }
+
+ return irq_rc;
+}
+
+static int qcom_llcc_edac_probe(struct platform_device *pdev)
+{
+ struct llcc_drv_data *llcc_driv_data = pdev->dev.platform_data;
+ struct edac_device_ctl_info *edev_ctl;
+ struct device *dev = &pdev->dev;
+ u32 ecc_irq;
+ int rc;
+
+ rc = qcom_llcc_core_setup(llcc_driv_data->bcast_regmap);
+ if (rc)
+ return rc;
+
+ /* Allocate edac control info */
+ edev_ctl = edac_device_alloc_ctl_info(0, "qcom-llcc", 1, "bank",
+ llcc_driv_data->num_banks, 1,
+ NULL, 0,
+ edac_device_alloc_index());
+
+ if (!edev_ctl)
+ return -ENOMEM;
+
+ edev_ctl->dev = dev;
+ edev_ctl->mod_name = dev_name(dev);
+ edev_ctl->dev_name = dev_name(dev);
+ edev_ctl->ctl_name = "llcc";
+ edev_ctl->panic_on_ue = LLCC_ERP_PANIC_ON_UE;
+
+ edev_ctl->pvt_info = (struct llcc_drv_data *) llcc_driv_data;
Why is that cast needed?
Not needed, redundant, the variable is already of that type. I'll check
if the cast is needed in the first line of this function.