PCI: dwc: Fix scheduling while atomic issues

When programming the inbound/outbound ATUs, we call usleep_range() after
each checking PCIE_ATU_ENABLE bit. Unfortunately, the ATU programming
can be executed in atomic context:

inbound ATU programming could be called through
pci_epc_write_header()
  =>dw_pcie_ep_write_header()
    =>dw_pcie_prog_inbound_atu()

outbound ATU programming could be called through
pci_bus_read_config_dword()
  =>dw_pcie_rd_conf()
    =>dw_pcie_prog_outbound_atu()

Fix this issue by calling mdelay() instead.

Fixes: f8aed6ec62 ("PCI: dwc: designware: Add EP mode support")
Fixes: d8bbeb39fb ("PCI: designware: Wait for iATU enable")
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
[lorenzo.pieralisi@arm.com: commit log update]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
This commit is contained in:
Jisheng Zhang 2018-09-20 16:32:52 -05:00 committed by Bjorn Helgaas
parent b3027b7746
commit 9024143e70
2 changed files with 5 additions and 6 deletions

View file

@ -135,7 +135,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, int index,
if (val & PCIE_ATU_ENABLE)
return;
usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX);
mdelay(LINK_WAIT_IATU);
}
dev_err(pci->dev, "Outbound iATU is not being enabled\n");
}
@ -178,7 +178,7 @@ void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type,
if (val & PCIE_ATU_ENABLE)
return;
usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX);
mdelay(LINK_WAIT_IATU);
}
dev_err(pci->dev, "Outbound iATU is not being enabled\n");
}
@ -236,7 +236,7 @@ static int dw_pcie_prog_inbound_atu_unroll(struct dw_pcie *pci, int index,
if (val & PCIE_ATU_ENABLE)
return 0;
usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX);
mdelay(LINK_WAIT_IATU);
}
dev_err(pci->dev, "Inbound iATU is not being enabled\n");
@ -282,7 +282,7 @@ int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int bar,
if (val & PCIE_ATU_ENABLE)
return 0;
usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX);
mdelay(LINK_WAIT_IATU);
}
dev_err(pci->dev, "Inbound iATU is not being enabled\n");

View file

@ -26,8 +26,7 @@
/* Parameters for the waiting for iATU enabled routine */
#define LINK_WAIT_MAX_IATU_RETRIES 5
#define LINK_WAIT_IATU_MIN 9000
#define LINK_WAIT_IATU_MAX 10000
#define LINK_WAIT_IATU 9
/* Synopsys-specific PCIe configuration registers */
#define PCIE_PORT_LINK_CONTROL 0x710