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Diffstat (limited to 'target/linux/ar71xx/patches-4.14/106-02-MIPS-ath79-do-AR724x-PCIe-root-complex-init.patch')
-rw-r--r--target/linux/ar71xx/patches-4.14/106-02-MIPS-ath79-do-AR724x-PCIe-root-complex-init.patch113
1 files changed, 113 insertions, 0 deletions
diff --git a/target/linux/ar71xx/patches-4.14/106-02-MIPS-ath79-do-AR724x-PCIe-root-complex-init.patch b/target/linux/ar71xx/patches-4.14/106-02-MIPS-ath79-do-AR724x-PCIe-root-complex-init.patch
new file mode 100644
index 0000000000..3af99bf3b5
--- /dev/null
+++ b/target/linux/ar71xx/patches-4.14/106-02-MIPS-ath79-do-AR724x-PCIe-root-complex-init.patch
@@ -0,0 +1,113 @@
+From 460f382c278fe66059a773c41cbcd0db86d53983 Mon Sep 17 00:00:00 2001
+From: Mathias Kresin <dev@kresin.me>
+Date: Thu, 13 Apr 2017 09:47:42 +0200
+Subject: [PATCH] MIPS: pci-ar724x: get PCIe controller out of reset
+
+The ar724x pci driver expects the PCIe controller to be brought out of
+reset by the bootloader.
+
+At least the AVM Fritz 300E bootloader doesn't take care of releasing
+the different PCIe controller related resets which causes an endless
+hang as soon as either the PCIE Reset register (0x180f0018) or the PCI
+Application Control register (0x180f0000) is read from.
+
+Do the full "PCIE Root Complex Initialization Sequence" if the PCIe
+host controller is still in reset during probing.
+
+The QCA u-boot sleeps 10ms after the PCIE Application Control bit is
+set to ready. It has been shown that 10ms might not be enough time if
+PCIe should be used right after setting the bit. During my tests it
+took up to 20ms till the link was up. Giving the link up to 100ms
+should work for all cases.
+
+Signed-off-by: Mathias Kresin <dev@kresin.me>
+---
+ arch/mips/include/asm/mach-ath79/ar71xx_regs.h | 3 ++
+ arch/mips/pci/pci-ar724x.c | 42 ++++++++++++++++++++++++++
+ 2 files changed, 45 insertions(+)
+
+--- a/arch/mips/include/asm/mach-ath79/ar71xx_regs.h
++++ b/arch/mips/include/asm/mach-ath79/ar71xx_regs.h
+@@ -169,6 +169,9 @@
+ #define AR724X_PLL_REG_CPU_CONFIG 0x00
+ #define AR724X_PLL_REG_PCIE_CONFIG 0x10
+
++#define AR724X_PLL_REG_PCIE_CONFIG_PPL_BYPASS BIT(16)
++#define AR724X_PLL_REG_PCIE_CONFIG_PPL_RESET BIT(25)
++
+ #define AR724X_PLL_FB_SHIFT 0
+ #define AR724X_PLL_FB_MASK 0x3ff
+ #define AR724X_PLL_REF_DIV_SHIFT 10
+--- a/arch/mips/pci/pci-ar724x.c
++++ b/arch/mips/pci/pci-ar724x.c
+@@ -12,14 +12,18 @@
+ #include <linux/irq.h>
+ #include <linux/pci.h>
+ #include <linux/init.h>
++#include <linux/delay.h>
+ #include <linux/platform_device.h>
+ #include <asm/mach-ath79/ath79.h>
+ #include <asm/mach-ath79/ar71xx_regs.h>
+
++#define AR724X_PCI_REG_APP 0x0
+ #define AR724X_PCI_REG_RESET 0x18
+ #define AR724X_PCI_REG_INT_STATUS 0x4c
+ #define AR724X_PCI_REG_INT_MASK 0x50
+
++#define AR724X_PCI_APP_LTSSM_ENABLE BIT(0)
++
+ #define AR724X_PCI_RESET_LINK_UP BIT(0)
+
+ #define AR724X_PCI_INT_DEV0 BIT(14)
+@@ -325,6 +329,37 @@ static void ar724x_pci_irq_init(struct a
+ apc);
+ }
+
++static void ar724x_pci_hw_init(struct ar724x_pci_controller *apc)
++{
++ u32 ppl, app;
++ int wait = 0;
++
++ /* deassert PCIe host controller and PCIe PHY reset */
++ ath79_device_reset_clear(AR724X_RESET_PCIE);
++ ath79_device_reset_clear(AR724X_RESET_PCIE_PHY);
++
++ /* remove the reset of the PCIE PLL */
++ ppl = ath79_pll_rr(AR724X_PLL_REG_PCIE_CONFIG);
++ ppl &= ~AR724X_PLL_REG_PCIE_CONFIG_PPL_RESET;
++ ath79_pll_wr(AR724X_PLL_REG_PCIE_CONFIG, ppl);
++
++ /* deassert bypass for the PCIE PLL */
++ ppl = ath79_pll_rr(AR724X_PLL_REG_PCIE_CONFIG);
++ ppl &= ~AR724X_PLL_REG_PCIE_CONFIG_PPL_BYPASS;
++ ath79_pll_wr(AR724X_PLL_REG_PCIE_CONFIG, ppl);
++
++ /* set PCIE Application Control to ready */
++ app = __raw_readl(apc->ctrl_base + AR724X_PCI_REG_APP);
++ app |= AR724X_PCI_APP_LTSSM_ENABLE;
++ __raw_writel(app, apc->ctrl_base + AR724X_PCI_REG_APP);
++
++ /* wait up to 100ms for PHY link up */
++ do {
++ mdelay(10);
++ wait++;
++ } while (wait < 10 && !ar724x_pci_check_link(apc));
++}
++
+ static int ar724x_pci_probe(struct platform_device *pdev)
+ {
+ struct ar724x_pci_controller *apc;
+@@ -383,6 +418,13 @@ static int ar724x_pci_probe(struct platf
+ apc->pci_controller.io_resource = &apc->io_res;
+ apc->pci_controller.mem_resource = &apc->mem_res;
+
++ /*
++ * Do the full PCIE Root Complex Initialization Sequence if the PCIe
++ * host controller is in reset.
++ */
++ if (ath79_reset_rr(AR724X_RESET_REG_RESET_MODULE) & AR724X_RESET_PCIE)
++ ar724x_pci_hw_init(apc);
++
+ apc->link_up = ar724x_pci_check_link(apc);
+ if (!apc->link_up)
+ dev_warn(&pdev->dev, "PCIe link is down\n");