openwrt/target/linux/airoha/patches-6.12/911-clk-en7581-Separate-PERST-from-refclk-in-PCIe-clock.patch

From: Ryan Chen <rchen14b@gmail.com>
Subject: clk: en7581: Separate PERST from refclk in PCIe clock callbacks

The EN7581 PCIe clock enable/disable callbacks currently toggle both
PERST (reset) and reference clock signals together. This prevents the
PCIe controller driver from properly sequencing PERST relative to MAC
register configuration, which is required for x2 link mode.

Separate the two concerns: clock callbacks only manage reference clocks
(REFCLK_EN0/EN1), while PERST (PERSTOUT/PERSTOUT1/PERSTOUT2) is left
to the PCIe controller driver to manage directly via the NP_SCU regmap.

Signed-off-by: Ryan Chen <rchen14b@gmail.com>
--- a/drivers/clk/clk-en7523.c
+++ b/drivers/clk/clk-en7523.c
@@ -960,9 +960,11 @@ static int en7581_pci_enable(struct clk_
 	struct regmap *map = cg->map;
 	u32 mask;
 
-	mask = REG_PCI_CONTROL_REFCLK_EN0 | REG_PCI_CONTROL_REFCLK_EN1 |
-	       REG_PCI_CONTROL_PERSTOUT1 | REG_PCI_CONTROL_PERSTOUT2 |
-	       REG_PCI_CONTROL_PERSTOUT;
+	/* Only enable reference clocks - PERST is managed separately by the
+	 * PCIe controller driver to allow proper sequencing of MAC register
+	 * configuration between PERST assert and deassert.
+	 */
+	mask = REG_PCI_CONTROL_REFCLK_EN0 | REG_PCI_CONTROL_REFCLK_EN1;
 	regmap_set_bits(map, REG_PCI_CONTROL, mask);
 
 	return 0;
@@ -974,9 +976,8 @@ static void en7581_pci_disable(struct cl
 	struct regmap *map = cg->map;
 	u32 mask;
 
-	mask = REG_PCI_CONTROL_REFCLK_EN0 | REG_PCI_CONTROL_REFCLK_EN1 |
-	       REG_PCI_CONTROL_PERSTOUT1 | REG_PCI_CONTROL_PERSTOUT2 |
-	       REG_PCI_CONTROL_PERSTOUT;
+	/* Only disable reference clocks - PCIe driver manages PERST */
+	mask = REG_PCI_CONTROL_REFCLK_EN0 | REG_PCI_CONTROL_REFCLK_EN1;
 	regmap_clear_bits(map, REG_PCI_CONTROL, mask);
 	usleep_range(1000, 2000);
 }