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| author | Pali Rohár <pali@kernel.org> | 2021-10-05 21:09:52 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-18 16:03:50 +0300 |
| commit | 5fb031fcd423bde73dccd3d752ca1f76fb23b503 (patch) | |
| tree | 00611cfe9f7c3617b93e1b30d43d3156984ef911 /drivers/pci/controller | |
| parent | 2b861523d7ceb88bf1ee36a0ab523f3d7ca03ca7 (diff) | |
| download | linux-5fb031fcd423bde73dccd3d752ca1f76fb23b503.tar.xz | |
PCI: aardvark: Fix reporting Data Link Layer Link Active
commit 2b650b7ff20eb7ea8ef9031d20fb657286ab90cc upstream.
Add support for reporting PCI_EXP_LNKSTA_DLLLA bit in Link Control register
on emulated bridge via current LTSSM state. Also correctly indicate DLLLA
capability via PCI_EXP_LNKCAP_DLLLARC bit in Link Control Capability
register.
Link: https://lore.kernel.org/r/20211005180952.6812-14-kabel@kernel.org
Fixes: 8a3ebd8de328 ("PCI: aardvark: Implement emulated root PCI bridge config space")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/pci/controller')
| -rw-r--r-- | drivers/pci/controller/pci-aardvark.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index 1ff6f0d68773..3225e288639f 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -328,6 +328,20 @@ static inline bool advk_pcie_link_up(struct advk_pcie *pcie) return ltssm_state >= LTSSM_L0 && ltssm_state < LTSSM_DISABLED; } +static inline bool advk_pcie_link_active(struct advk_pcie *pcie) +{ + /* + * According to PCIe Base specification 3.0, Table 4-14: Link + * Status Mapped to the LTSSM, and 4.2.6.3.6 Configuration.Idle + * is Link Up mapped to LTSSM Configuration.Idle, Recovery, L0, + * L0s, L1 and L2 states. And according to 3.2.1. Data Link + * Control and Management State Machine Rules is DL Up status + * reported in DL Active state. + */ + u8 ltssm_state = advk_pcie_ltssm_state(pcie); + return ltssm_state >= LTSSM_CONFIG_IDLE && ltssm_state < LTSSM_DISABLED; +} + static inline bool advk_pcie_link_training(struct advk_pcie *pcie) { /* @@ -798,12 +812,26 @@ advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, return PCI_BRIDGE_EMUL_HANDLED; } + case PCI_EXP_LNKCAP: { + u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg); + /* + * PCI_EXP_LNKCAP_DLLLARC bit is hardwired in aardvark HW to 0. + * But support for PCI_EXP_LNKSTA_DLLLA is emulated via ltssm + * state so explicitly enable PCI_EXP_LNKCAP_DLLLARC flag. + */ + val |= PCI_EXP_LNKCAP_DLLLARC; + *value = val; + return PCI_BRIDGE_EMUL_HANDLED; + } + case PCI_EXP_LNKCTL: { /* u32 contains both PCI_EXP_LNKCTL and PCI_EXP_LNKSTA */ u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg) & ~(PCI_EXP_LNKSTA_LT << 16); if (advk_pcie_link_training(pcie)) val |= (PCI_EXP_LNKSTA_LT << 16); + if (advk_pcie_link_active(pcie)) + val |= (PCI_EXP_LNKSTA_DLLLA << 16); *value = val; return PCI_BRIDGE_EMUL_HANDLED; } @@ -811,7 +839,6 @@ advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, case PCI_CAP_LIST_ID: case PCI_EXP_DEVCAP: case PCI_EXP_DEVCTL: - case PCI_EXP_LNKCAP: *value = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg); return PCI_BRIDGE_EMUL_HANDLED; default: |