@@ -13,12 +13,14 @@
#include <linux/bitops.h>
#include <linux/clk.h>
+#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/init.h>
+#include <linux/iopoll.h>
#include <linux/msi.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
@@ -41,6 +43,21 @@ struct rcar_msi {
int irq2;
};
+#ifdef CONFIG_ARM
+/*
+ * Here we keep a static copy of the remapped PCIe controller address.
+ * This is only used on aarch32 systems, all of which have one single
+ * PCIe controller, to provide quick access to the PCIe controller in
+ * the L1 link state fixup function, called from the ARM fault handler.
+ */
+static void __iomem *pcie_base;
+/*
+ * Static copy of bus clock pointer, so we can check whether the clock
+ * is enabled or not.
+ */
+static struct clk *pcie_bus_clk;
+#endif
+
/* Structure representing the PCIe interface */
struct rcar_pcie_host {
struct rcar_pcie pcie;
@@ -774,6 +791,12 @@ static int rcar_pcie_get_resources(struct rcar_pcie_host *host)
}
host->msi.irq2 = i;
+#ifdef CONFIG_ARM
+ /* Cache static copy for L1 link state fixup hook on aarch32 */
+ pcie_base = pcie->base;
+ pcie_bus_clk = host->bus_clk;
+#endif
+
return 0;
err_irq2:
@@ -1029,4 +1052,67 @@ static struct platform_driver rcar_pcie_driver = {
},
.probe = rcar_pcie_probe,
};
+
+#ifdef CONFIG_ARM
+static DEFINE_SPINLOCK(pmsr_lock);
+static int rcar_pcie_aarch32_abort_handler(unsigned long addr,
+ unsigned int fsr, struct pt_regs *regs)
+{
+ unsigned long flags;
+ u32 pmsr, val;
+ int ret = 0;
+
+ spin_lock_irqsave(&pmsr_lock, flags);
+
+ if (!pcie_base || !__clk_is_enabled(pcie_bus_clk)) {
+ ret = 1;
+ goto unlock_exit;
+ }
+
+ pmsr = readl(pcie_base + PMSR);
+
+ /*
+ * Test if the PCIe controller received PM_ENTER_L1 DLLP and
+ * the PCIe controller is not in L1 link state. If true, apply
+ * fix, which will put the controller into L1 link state, from
+ * which it can return to L0s/L0 on its own.
+ */
+ if ((pmsr & PMEL1RX) && ((pmsr & PMSTATE) != PMSTATE_L1)) {
+ writel(L1IATN, pcie_base + PMCTLR);
+ ret = readl_poll_timeout_atomic(pcie_base + PMSR, val,
+ val & L1FAEG, 10, 1000);
+ WARN(ret, "Timeout waiting for L1 link state, ret=%d\n", ret);
+ writel(L1FAEG | PMEL1RX, pcie_base + PMSR);
+ }
+
+unlock_exit:
+ spin_unlock_irqrestore(&pmsr_lock, flags);
+ return ret;
+}
+
+static const struct of_device_id rcar_pcie_abort_handler_of_match[] __initconst = {
+ { .compatible = "renesas,pcie-r8a7779" },
+ { .compatible = "renesas,pcie-r8a7790" },
+ { .compatible = "renesas,pcie-r8a7791" },
+ { .compatible = "renesas,pcie-rcar-gen2" },
+ {},
+};
+
+static int __init rcar_pcie_init(void)
+{
+ if (of_find_matching_node(NULL, rcar_pcie_abort_handler_of_match)) {
+#ifdef CONFIG_ARM_LPAE
+ hook_fault_code(17, rcar_pcie_aarch32_abort_handler, SIGBUS, 0,
+ "asynchronous external abort");
+#else
+ hook_fault_code(22, rcar_pcie_aarch32_abort_handler, SIGBUS, 0,
+ "imprecise external abort");
+#endif
+ }
+
+ return platform_driver_register(&rcar_pcie_driver);
+}
+device_initcall(rcar_pcie_init);
+#else
builtin_platform_driver(rcar_pcie_driver);
+#endif
@@ -85,6 +85,13 @@
#define LTSMDIS BIT(31)
#define MACCTLR_INIT_VAL (LTSMDIS | MACCTLR_NFTS_MASK)
#define PMSR 0x01105c
+#define L1FAEG BIT(31)
+#define PMEL1RX BIT(23)
+#define PMSTATE GENMASK(18, 16)
+#define PMSTATE_L1 (3 << 16)
+#define PMCTLR 0x011060
+#define L1IATN BIT(31)
+
#define MACS2R 0x011078
#define MACCGSPSETR 0x011084
#define SPCNGRSN BIT(31)