[PATCH AUTOSEL 5.17 56/60] Revert "PCI: brcmstb: Split brcm_pcie_setup() into two funcs"

Sasha Levin
2022-06-07T19:19:38Z

From: Bjorn Helgaas <bhelgaas@google.com>

[ Upstream commit f4fd559de3434c44bed1d2912bd0c75cfa42898b ]

This reverts commit 830aa6f29f07a4e2f1a947dfa72b3ccddb46dd21.

This is part of a revert of the following commits:

11ed8b8624b8 ("PCI: brcmstb: Do not turn off WOL regulators on suspend")
93e41f3fca3d ("PCI: brcmstb: Add control of subdevice voltage regulators")
67211aadcb4b ("PCI: brcmstb: Add mechanism to turn on subdev regulators")
830aa6f29f07 ("PCI: brcmstb: Split brcm_pcie_setup() into two funcs")

Cyril reported that 830aa6f29f07 ("PCI: brcmstb: Split brcm_pcie_setup()
into two funcs"), which appeared in v5.17-rc1, broke booting on the
Raspberry Pi Compute Module 4. Apparently 830aa6f29f07 panics with an
Asynchronous SError Interrupt, and after further commits here is a black
screen on HDMI and no output on the serial console.

This does not seem to affect the Raspberry Pi 4 B.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215925
Link: https://lore.kernel.org/r/20220511201856.808690-5-helgaas@kernel.org
Reported-by: Cyril Brulebois <kibi@debian.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/controller/pcie-brcmstb.c | 65 +++++++++++----------------
1 file changed, 26 insertions(+), 39 deletions(-)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 0e8346114a8d..e61058e13818 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -926,9 +926,16 @@ static inline int brcm_pcie_get_rc_bar2_size_and_offset(struct brcm_pcie *pcie,

static int brcm_pcie_setup(struct brcm_pcie *pcie)
{
+ struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
u64 rc_bar2_offset, rc_bar2_size;
void __iomem *base = pcie->base;
- int ret, memc;
+ struct device *dev = pcie->dev;
+ struct resource_entry *entry;
+ bool ssc_good = false;
+ struct resource *res;
+ int num_out_wins = 0;
+ u16 nlw, cls, lnksta;
+ int i, ret, memc;
u32 tmp, burst, aspm_support;

/* Reset the bridge */
@@ -1018,40 +1025,6 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie)
if (pcie->gen)
brcm_pcie_set_gen(pcie, pcie->gen);

- /* Don't advertise L0s capability if 'aspm-no-l0s' */
- aspm_support = PCIE_LINK_STATE_L1;
- if (!of_property_read_bool(pcie->np, "aspm-no-l0s"))
- aspm_support |= PCIE_LINK_STATE_L0S;
- tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
- u32p_replace_bits(&tmp, aspm_support,
- PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK);
- writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
-
- /*
- * For config space accesses on the RC, show the right class for
- * a PCIe-PCIe bridge (the default setting is to be EP mode).
- */
- tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3);
- u32p_replace_bits(&tmp, 0x060400,
- PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK);
- writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3);
-
- return 0;
-}
-
-static int brcm_pcie_linkup(struct brcm_pcie *pcie)
-{
- struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
- struct device *dev = pcie->dev;
- void __iomem *base = pcie->base;
- struct resource_entry *entry;
- struct resource *res;
- int num_out_wins = 0;
- u16 nlw, cls, lnksta;
- bool ssc_good = false;
- u32 tmp;
- int ret, i;
-
/* Unassert the fundamental reset */
pcie->perst_set(pcie, 0);

@@ -1102,6 +1075,24 @@ static int brcm_pcie_linkup(struct brcm_pcie *pcie)
num_out_wins++;
}

+ /* Don't advertise L0s capability if 'aspm-no-l0s' */
+ aspm_support = PCIE_LINK_STATE_L1;
+ if (!of_property_read_bool(pcie->np, "aspm-no-l0s"))
+ aspm_support |= PCIE_LINK_STATE_L0S;
+ tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
+ u32p_replace_bits(&tmp, aspm_support,
+ PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK);
+ writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
+
+ /*
+ * For config space accesses on the RC, show the right class for
+ * a PCIe-PCIe bridge (the default setting is to be EP mode).
+ */
+ tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3);
+ u32p_replace_bits(&tmp, 0x060400,
+ PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK);
+ writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3);
+
if (pcie->ssc) {
ret = brcm_pcie_set_ssc(pcie);
if (ret == 0)
@@ -1290,10 +1281,6 @@ static int brcm_pcie_resume(struct device *dev)
if (ret)
goto err_reset;

- ret = brcm_pcie_linkup(pcie);
- if (ret)
- goto err_reset;
-
if (pcie->msi)
brcm_msi_set_regs(pcie->msi);

--
2.35.1