Merge tag 'loongarch-kvm-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.18

1. Add PTW feature detection on new hardware.
2. Add sign extension with kernel MMIO/IOCSR emulation.
3. Improve in-kernel IPI emulation.
4. Improve in-kernel PCH-PIC emulation.
5. Move kvm_iocsr tracepoint out of generic code.

1 files changed, 19 insertions, 6 deletions

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
index 95830dcfdec9..0fa63b734b67 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
@@ -3067,6 +3067,14 @@ struct qmp_pcie {
 	struct clk_fixed_rate aux_clk_fixed;
 };
 
+static bool qphy_checkbits(const void __iomem *base, u32 offset, u32 val)
+{
+	u32 reg;
+
+	reg = readl(base + offset);
+	return (reg & val) == val;
+}
+
 static inline void qphy_setbits(void __iomem *base, u32 offset, u32 val)
 {
 	u32 reg;
@@ -4339,16 +4347,21 @@ static int qmp_pcie_init(struct phy *phy)
 	struct qmp_pcie *qmp = phy_get_drvdata(phy);
 	const struct qmp_phy_cfg *cfg = qmp->cfg;
 	void __iomem *pcs = qmp->pcs;
-	bool phy_initialized = !!(readl(pcs + cfg->regs[QPHY_START_CTRL]));
 	int ret;
 
-	qmp->skip_init = qmp->nocsr_reset && phy_initialized;
 	/*
-	 * We need to check the existence of init sequences in two cases:
-	 * 1. The PHY doesn't support no_csr reset.
-	 * 2. The PHY supports no_csr reset but isn't initialized by bootloader.
-	 * As we can't skip init in these two cases.
+	 * We can skip PHY initialization if all of the following conditions
+	 * are met:
+	 *  1. The PHY supports the nocsr_reset that preserves the PHY config.
+	 *  2. The PHY was started (and not powered down again) by the
+	 *     bootloader, with all of the expected bits set correctly.
+	 * In this case, we can continue without having the init sequence
+	 * defined in the driver.
 	 */
+	qmp->skip_init = qmp->nocsr_reset &&
+		qphy_checkbits(pcs, cfg->regs[QPHY_START_CTRL], SERDES_START | PCS_START) &&
+		qphy_checkbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL], cfg->pwrdn_ctrl);
+
 	if (!qmp->skip_init && !cfg->tbls.serdes_num) {
 		dev_err(qmp->dev, "Init sequence not available\n");
 		return -ENODATA;