[PATCH 1/4] mmc: mtk-sd: Clarify patch bit register initialization and layout

From: AngeloGioacchino Del Regno
Date: Tue Mar 25 2025 - 07:07:32 EST


In preparation for cleaning up the msdc_init_hw register setting
for the patch bit registers, add the necessary definitions for
bits in the MSDC_PATCH_BIT and MSDC_PATCH_BIT1 registers and use
them in place of "magic numbers" writes during initialization.

This commit brings no functional differences.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
---
drivers/mmc/host/mtk-sd.c | 61 +++++++++++++++++++++++++++++++++++----
1 file changed, 55 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index 345ea91629e0..04471a7ef078 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -5,6 +5,7 @@
*/

#include <linux/module.h>
+#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
@@ -233,7 +234,9 @@

/* MSDC_PATCH_BIT mask */
#define MSDC_PATCH_BIT_ODDSUPP BIT(1) /* RW */
+#define MSDC_PATCH_BIT_DIS_WRMON BIT(2) /* RW */
#define MSDC_PATCH_BIT_RD_DAT_SEL BIT(3) /* RW */
+#define MSDC_PATCH_BIT_DESCUP_SEL BIT(6) /* RW */
#define MSDC_INT_DAT_LATCH_CK_SEL GENMASK(9, 7)
#define MSDC_CKGEN_MSDC_DLY_SEL GENMASK(14, 10)
#define MSDC_PATCH_BIT_IODSSEL BIT(16) /* RW */
@@ -246,10 +249,22 @@
#define MSDC_PATCH_BIT_SPCPUSH BIT(29) /* RW */
#define MSDC_PATCH_BIT_DECRCTMO BIT(30) /* RW */

-#define MSDC_PATCH_BIT1_CMDTA GENMASK(5, 3) /* RW */
+/* MSDC_PATCH_BIT1 mask */
+#define MSDC_PB1_WRDAT_CRC_TACNTR GENMASK(2, 0) /* RW */
+#define MSDC_PATCH_BIT1_CMDTA GENMASK(5, 3) /* RW */
#define MSDC_PB1_BUSY_CHECK_SEL BIT(7) /* RW */
#define MSDC_PATCH_BIT1_STOP_DLY GENMASK(11, 8) /* RW */
-
+#define MSDC_PB1_DDR_CMD_FIX_SEL BIT(14) /* RW */
+#define MSDC_PB1_SINGLE_BURST BIT(16) /* RW */
+#define MSDC_PB1_RSVD20 GENMASK(18, 17) /* RW */
+#define MSDC_PB1_AUTO_SYNCST_CLR BIT(19) /* RW */
+#define MSDC_PB1_MARK_POP_WATER BIT(20) /* RW */
+#define MSDC_PB1_LP_DCM_EN BIT(21) /* RW */
+#define MSDC_PB1_RSVD3 BIT(22) /* RW */
+#define MSDC_PB1_AHB_GDMA_HCLK BIT(23) /* RW */
+#define MSDC_PB1_MSDC_CLK_ENFEAT GENMASK(31, 24) /* RW */
+
+/* MSDC_PATCH_BIT2 mask */
#define MSDC_PATCH_BIT2_CFGRESP BIT(15) /* RW */
#define MSDC_PATCH_BIT2_CFGCRCSTS BIT(28) /* RW */
#define MSDC_PB2_SUPPORT_64G BIT(1) /* RW */
@@ -1816,7 +1831,7 @@ static irqreturn_t msdc_irq(int irq, void *dev_id)

static void msdc_init_hw(struct msdc_host *host)
{
- u32 val;
+ u32 val, pb1_val;
u32 tune_reg = host->dev_comp->pad_tune_reg;
struct mmc_host *mmc = mmc_from_priv(host);

@@ -1869,9 +1884,43 @@ static void msdc_init_hw(struct msdc_host *host)
}
writel(0, host->base + MSDC_IOCON);
sdr_set_field(host->base + MSDC_IOCON, MSDC_IOCON_DDLSEL, 0);
- writel(0x403c0046, host->base + MSDC_PATCH_BIT);
- sdr_set_field(host->base + MSDC_PATCH_BIT, MSDC_CKGEN_MSDC_DLY_SEL, 1);
- writel(0xffff4089, host->base + MSDC_PATCH_BIT1);
+
+ /* Enable odd number support for 8-bit data bus */
+ val = MSDC_PATCH_BIT_ODDSUPP;
+
+ /* Disable SD command register write monitor */
+ val |= MSDC_PATCH_BIT_DIS_WRMON;
+
+ /* Issue transfer done interrupt after GPD update */
+ val |= MSDC_PATCH_BIT_DESCUP_SEL;
+
+ /* Extend R1B busy detection delay (in clock cycles) */
+ val |= FIELD_PREP(MSDC_PATCH_BIT_BUSYDLY, 15);
+
+ /* Enable CRC phase timeout during data write operation */
+ val |= MSDC_PATCH_BIT_DECRCTMO;
+
+ /* Set CKGEN delay to one stage */
+ val |= FIELD_PREP(MSDC_CKGEN_MSDC_DLY_SEL, 1);
+ writel(val, host->base + MSDC_PATCH_BIT);
+
+ /* Set wr data, crc status, cmd response turnaround period for UHS104 */
+ pb1_val = FIELD_PREP(MSDC_PB1_WRDAT_CRC_TACNTR, 1);
+ pb1_val |= FIELD_PREP(MSDC_PATCH_BIT1_CMDTA, 1);
+ pb1_val |= MSDC_PB1_DDR_CMD_FIX_SEL;
+
+ /* Set single burst mode, auto sync state clear, block gap stop clk */
+ pb1_val |= MSDC_PB1_SINGLE_BURST | MSDC_PB1_RSVD20 |
+ MSDC_PB1_AUTO_SYNCST_CLR | MSDC_PB1_MARK_POP_WATER;
+
+ /* Set low power DCM, use HCLK for GDMA, use MSDC CLK for everything else */
+ pb1_val |= MSDC_PB1_LP_DCM_EN | MSDC_PB1_RSVD3 |
+ MSDC_PB1_AHB_GDMA_HCLK | MSDC_PB1_MSDC_CLK_ENFEAT;
+
+ /* Enable R1b command busy check */
+ pb1_val |= MSDC_PB1_BUSY_CHECK_SEL;
+ writel(pb1_val, host->base + MSDC_PATCH_BIT1);
+
sdr_set_bits(host->base + EMMC50_CFG0, EMMC50_CFG_CFCSTS_SEL);

if (host->dev_comp->stop_clk_fix) {
--
2.48.1