From 2412c1968777a0fe77cb24dda935e3414e00ebb1 Mon Sep 17 00:00:00 2001 From: Yan Wang Date: Tue, 8 Feb 2022 16:10:31 +0800 Subject: [PATCH 5/6] pcie: Add pcie-root-port fast plug/unplug feature If a device is plugged in the pcie-root-port when VM kernel is booting, the kernel may wrongly disable the device. This bug was brought in by two patches of the linux kernel: https://patchwork.kernel.org/patch/10575355/ https://patchwork.kernel.org/patch/10766219/ VM runtime like kata uses this feature to boot microVM, so we must fix it up. We hack into the pcie native hotplug patch so that hotplug/unplug will work under this circumstance. Signed-off-by: Ying Fang Signed-off-by: Yan Wang --- hw/core/machine.c | 2 ++ hw/pci-bridge/gen_pcie_root_port.c | 2 ++ hw/pci/pcie.c | 13 ++++++++++++- include/hw/pci/pcie_port.h | 3 +++ 4 files changed, 19 insertions(+), 1 deletion(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index 53a99ab..126e3e2 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -121,6 +121,8 @@ const size_t hw_compat_4_0_len = G_N_ELEMENTS(hw_compat_4_0); GlobalProperty hw_compat_3_1[] = { { "pcie-root-port", "x-speed", "2_5" }, { "pcie-root-port", "x-width", "1" }, + { "pcie-root-port", "fast-plug", "0" }, + { "pcie-root-port", "fast-unplug", "0" }, { "memory-backend-file", "x-use-canonical-path-for-ramblock-id", "true" }, { "memory-backend-memfd", "x-use-canonical-path-for-ramblock-id", "true" }, { "tpm-crb", "ppi", "false" }, diff --git a/hw/pci-bridge/gen_pcie_root_port.c b/hw/pci-bridge/gen_pcie_root_port.c index 20099a8..0bf9df9 100644 --- a/hw/pci-bridge/gen_pcie_root_port.c +++ b/hw/pci-bridge/gen_pcie_root_port.c @@ -140,6 +140,8 @@ static Property gen_rp_props[] = { speed, PCIE_LINK_SPEED_16), DEFINE_PROP_PCIE_LINK_WIDTH("x-width", PCIESlot, width, PCIE_LINK_WIDTH_32), + DEFINE_PROP_UINT8("fast-plug", PCIESlot, fast_plug, 0), + DEFINE_PROP_UINT8("fast-unplug", PCIESlot, fast_unplug, 0), DEFINE_PROP_END_OF_LIST() }; diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c index d7d73a3..d7d1504 100644 --- a/hw/pci/pcie.c +++ b/hw/pci/pcie.c @@ -526,6 +526,7 @@ void pcie_cap_slot_unplug_request_cb(HotplugHandler *hotplug_dev, uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap; uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP); uint16_t sltctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL); + PCIESlot *s = PCIE_SLOT(hotplug_pdev); /* Check if hot-unplug is disabled on the slot */ if ((sltcap & PCI_EXP_SLTCAP_HPC) == 0) { @@ -572,7 +573,17 @@ void pcie_cap_slot_unplug_request_cb(HotplugHandler *hotplug_dev, return; } - pcie_cap_slot_push_attention_button(hotplug_pdev); + if ((pci_dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) && s->fast_plug) { + pci_word_test_and_clear_mask(pci_dev->config + pci_dev->exp.exp_cap + PCI_EXP_LNKSTA, + PCI_EXP_LNKSTA_DLLLA); + } + + if (s->fast_unplug) { + pcie_cap_slot_event(hotplug_pdev, + PCI_EXP_HP_EV_PDC | PCI_EXP_HP_EV_ABP); + } else { + pcie_cap_slot_push_attention_button(hotplug_pdev); + } } /* pci express slot for pci express root/downstream port diff --git a/include/hw/pci/pcie_port.h b/include/hw/pci/pcie_port.h index e25b289..5b80a13 100644 --- a/include/hw/pci/pcie_port.h +++ b/include/hw/pci/pcie_port.h @@ -51,6 +51,9 @@ struct PCIESlot { uint8_t chassis; uint16_t slot; + uint8_t fast_plug; + uint8_t fast_unplug; + PCIExpLinkSpeed speed; PCIExpLinkWidth width; -- 1.9.1