scsi: ufs: core: Fix interrupt handling for MCQ Mode

Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service
routine to a threaded IRQ handler") introduced a regression where the UFS
interrupt status register (IS) was not cleared in ufshcd_intr() when
operating in MCQ mode. As a result, the IS register remained uncleared.

This led to a persistent issue during UIC interrupts:
ufshcd_is_auto_hibern8_error() consistently returned true because the
UFSHCD_UIC_HIBERN8_MASK bit was set, while the active command was neither
UIC_CMD_DME_HIBER_ENTER nor UIC_CMD_DME_HIBER_EXIT. This caused
continuous auto hibern8 enter errors and device failed to boot.

To fix this, ensure that the interrupt status register is properly
cleared in the ufshcd_intr() function for both MCQ mode with ESI enabled.

[    4.553226] ufshcd-qcom 1d84000.ufs: ufshcd_check_errors: Auto
Hibern8 Enter failed - status: 0x00000040, upmcrs: 0x00000001
[    4.553229] ufshcd-qcom 1d84000.ufs: ufshcd_check_errors: saved_err
0x40 saved_uic_err 0x0
[    4.553311] host_regs: 00000000: d5c7033f 20e0071f 00000400 00000000
[    4.553312] host_regs: 00000010: 01000000 00010217 00000c96 00000000
[    4.553314] host_regs: 00000020: 00000440 00170ef5 00000000 00000000
[    4.553316] host_regs: 00000030: 0000010f 00000001 00000000 00000000
[    4.553317] host_regs: 00000040: 00000000 00000000 00000000 00000000
[    4.553319] host_regs: 00000050: fffdf000 0000000f 00000000 00000000
[    4.553320] host_regs: 00000060: 00000001 80000000 00000000 00000000
[    4.553322] host_regs: 00000070: fffde000 0000000f 00000000 00000000
[    4.553323] host_regs: 00000080: 00000001 00000000 00000000 00000000
[    4.553325] host_regs: 00000090: 00000002 d0020000 00000000 01930200

Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler")
Co-developed-by: Palash Kambar <[email protected]>
Signed-off-by: Palash Kambar <[email protected]>
Signed-off-by: Nitin Rawat <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Tested-by: Neil Armstrong <[email protected]> # on SM8650-QRD
Reviewed-by: Bart Van Assche <[email protected]>
Reviewed-by: Peter Wang <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Nitin Rawat

drivers/ufs/core/ufshcd.c

@@ -7133,14 +7133,19 @@ static irqreturn_t ufshcd_threaded_intr(int irq, void *__hba)
 static irqreturn_t ufshcd_intr(int irq, void *__hba)
 {
 	struct ufs_hba *hba = __hba;
+	u32 intr_status, enabled_intr_status;
 
 	/* Move interrupt handling to thread when MCQ & ESI are not enabled */
 	if (!hba->mcq_enabled || !hba->mcq_esi_enabled)
 		return IRQ_WAKE_THREAD;
 
+	intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS);
+	enabled_intr_status = intr_status & ufshcd_readl(hba, REG_INTERRUPT_ENABLE);
+
+	ufshcd_writel(hba, intr_status, REG_INTERRUPT_STATUS);
+
 	/* Directly handle interrupts since MCQ ESI handlers does the hard job */
-	return ufshcd_sl_intr(hba, ufshcd_readl(hba, REG_INTERRUPT_STATUS) &
-				   ufshcd_readl(hba, REG_INTERRUPT_ENABLE));
+	return ufshcd_sl_intr(hba, enabled_intr_status);
 }
 
 static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag)