Re: [PATCH V3 3/3] scsi: ufs-qcom: Add support for testbus registers

[Manivannan Sadhasivam]

On Thu, Mar 13, 2025 at 10:46:35AM +0530, Manish Pandey wrote:
> This patch introduces support for dumping testbus registers,
> enhancing the debugging capabilities for UFS-QCOM drivers.
> 

Same comment as patch 1.

> Signed-off-by: Manish Pandey <quic_mapa@xxxxxxxxxxx>
> ---
> Changes in v3:
> - Annotated the 'testbus' declaration with __free.
> - Converted the switch-statements into an array lookup.
> - Introduced struct testbus_info{} for handling testbus switch-statements to an array lookup.
> Changes in v2:
> - Rebased patchsets.
> - Link to v1: https://lore.kernel.org/linux-arm-msm/20241025055054.23170-1-quic_mapa@xxxxxxxxxxx/
> 
> ---
>  drivers/ufs/host/ufs-qcom.c | 53 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 52 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
> index fb9da04c0d35..c32b1268d299 100644
> --- a/drivers/ufs/host/ufs-qcom.c
> +++ b/drivers/ufs/host/ufs-qcom.c
> @@ -17,6 +17,7 @@
>  #include <linux/time.h>
>  #include <linux/unaligned.h>
>  #include <linux/units.h>
> +#include <linux/cleanup.h>

Sort includes alphabetically.

>  
>  #include <soc/qcom/ice.h>
>  
> @@ -98,6 +99,24 @@ static const struct __ufs_qcom_bw_table {
>  	[MODE_MAX][0][0]		    = { 7643136,	819200 },
>  };
>  
> +static const struct {
> +	int nminor;
> +	char *prefix;
> +} testbus_info[TSTBUS_MAX] = {
> +	[TSTBUS_UAWM]     = {32, "TSTBUS_UAWM "},
> +	[TSTBUS_UARM]     = {32, "TSTBUS_UARM "},
> +	[TSTBUS_TXUC]     = {32, "TSTBUS_TXUC "},
> +	[TSTBUS_RXUC]     = {32, "TSTBUS_RXUC "},
> +	[TSTBUS_DFC]      = {32, "TSTBUS_DFC "},
> +	[TSTBUS_TRLUT]    = {32, "TSTBUS_TRLUT "},
> +	[TSTBUS_TMRLUT]   = {32, "TSTBUS_TMRLUT "},
> +	[TSTBUS_OCSC]     = {32, "TSTBUS_OCSC "},
> +	[TSTBUS_UTP_HCI]  = {32, "TSTBUS_UTP_HCI "},
> +	[TSTBUS_COMBINED] = {32, "TSTBUS_COMBINED "},
> +	[TSTBUS_WRAPPER]  = {32, "TSTBUS_WRAPPER "},
> +	[TSTBUS_UNIPRO]   = {256, "TSTBUS_UNIPRO "}
> +};
> +
>  static void ufs_qcom_get_default_testbus_cfg(struct ufs_qcom_host *host);
>  static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba, unsigned long freq);
>  
> @@ -1566,6 +1585,33 @@ int ufs_qcom_testbus_config(struct ufs_qcom_host *host)
>  	return 0;
>  }
>  
> +static void ufs_qcom_dump_testbus(struct ufs_hba *hba)
> +{
> +	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> +	int i, j, nminor = 0, testbus_len = 0;
> +	u32 *testbus __free(kfree) = NULL;
> +	char *prefix;
> +
> +	testbus = kmalloc(256 * sizeof(u32), GFP_KERNEL);

Use kmalloc_array().

> +	if (!testbus)
> +		return;
> +
> +	for (j = 0; j < TSTBUS_MAX; j++) {
> +		nminor = testbus_info[j].nminor;
> +		prefix = testbus_info[j].prefix;
> +		host->testbus.select_major = j;
> +		testbus_len = nminor * sizeof(u32);
> +		for (i = 0; i < nminor; i++) {
> +			host->testbus.select_minor = i;
> +			ufs_qcom_testbus_config(host);
> +			testbus[i] = ufshcd_readl(hba, UFS_TEST_BUS);
> +			usleep_range(100, 200);

Why this delay is required?

> +		}
> +		print_hex_dump(KERN_ERR, prefix, DUMP_PREFIX_OFFSET,
> +				16, 4, testbus, testbus_len, false);
> +	}
> +}
> +
>  static void ufs_qcom_dump_mcq_hci_regs(struct ufs_hba *hba)
>  {
>  	/* sleep intermittently to prevent CPU hog during data dumps. */
> @@ -1680,9 +1726,14 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba)
>  
>  	/* ensure below dumps occur only in task context due to blocking calls. */
>  	if (in_task()) {
> -		/* Dump MCQ Host Vendor Specific Registers */
> +		/* dump MCQ Host Vendor Specific Registers */

Spurious change.

>  		if (hba->mcq_enabled)
>  			ufs_qcom_dump_mcq_hci_regs(hba);
> +
> +		/* sleep a bit intermittently as we are dumping too much data */
> +		ufshcd_dump_regs(hba, UFS_TEST_BUS, 4, "UFS_TEST_BUS ");
> +		usleep_range(1000, 1100);

Same comment as previous patch. Use cond_resched().

- Mani

-- 
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