linux-kernel - [PATCH] soc: qcom: geni-se: Do not bother about enable/disable of interrupts in secondary sequencer for non-uart modes

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Message-Id: <1685729609-26871-1-git-send-email-quic_vnivarth@quicinc.com>
Date:   Fri,  2 Jun 2023 23:43:29 +0530
From:   Vijaya Krishna Nivarthi <quic_vnivarth@...cinc.com>
To:     agross@...nel.org, andersson@...nel.org, konrad.dybcio@...aro.org,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     quic_msavaliy@...cinc.com, dianders@...omium.org, mka@...omium.org,
        swboyd@...omium.org, quic_vtanuku@...cinc.com,
        Vijaya Krishna Nivarthi <quic_vnivarth@...cinc.com>
Subject: [PATCH] soc: qcom: geni-se: Do not bother about enable/disable of interrupts in secondary sequencer for non-uart modes

The select_fifo/dma_mode() functions in geni driver enable/disable
interrupts (secondary included) conditionally for non-uart modes, while
uart is supposed to manage this internally.
However, only uart uses secondary IRQs while spi, i2c do not care about
these at all making their enablement (or disablement) totally unnecessary
for these protos.

Drop enabling/disabling secondary IRQs for non-uart modes.
This doesn't solve any observed problem but only gets rid of code pieces
that are not required.

Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@...cinc.com>
---
 drivers/soc/qcom/qcom-geni-se.c | 24 ++++--------------------
 1 file changed, 4 insertions(+), 20 deletions(-)

diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
index 795a2e1..7111661 100644
--- a/drivers/soc/qcom/qcom-geni-se.c
+++ b/drivers/soc/qcom/qcom-geni-se.c
@@ -281,27 +281,14 @@ static void geni_se_select_fifo_mode(struct geni_se *se)
 
 	geni_se_irq_clear(se);
 
-	/*
-	 * The RX path for the UART is asynchronous and so needs more
-	 * complex logic for enabling / disabling its interrupts.
-	 *
-	 * Specific notes:
-	 * - The done and TX-related interrupts are managed manually.
-	 * - We don't RX from the main sequencer (we use the secondary) so
-	 *   we don't need the RX-related interrupts enabled in the main
-	 *   sequencer for UART.
-	 */
+	/* UART driver manages enabling / disabling interrupts internally */
 	if (proto != GENI_SE_UART) {
+		/* Non-UART use only primary sequencer so dont bother about S_IRQ */
 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
 		val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
 		val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
 		if (val != val_old)
 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
-
-		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
-		val |= S_CMD_DONE_EN;
-		if (val != val_old)
-			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
 	}
 
 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
@@ -317,17 +304,14 @@ static void geni_se_select_dma_mode(struct geni_se *se)
 
 	geni_se_irq_clear(se);
 
+	/* UART driver manages enabling / disabling interrupts internally */
 	if (proto != GENI_SE_UART) {
+		/* Non-UART use only primary sequencer so dont bother about S_IRQ */
 		val_old = val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
 		val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
 		val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
 		if (val != val_old)
 			writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
-
-		val_old = val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
-		val &= ~S_CMD_DONE_EN;
-		if (val != val_old)
-			writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
 	}
 
 	val_old = val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
-- 
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