[PATCH] 85xxCDS: Make sure restart resets the PCI bus.
From: Randy Vinson <hidden>
Date: 2007-06-07 20:38:08
Subsystem:
linux for powerpc (32-bit and 64-bit), linux for powerpc embedded ppc85xx, the rest · Maintainers:
Madhavan Srinivasan, Scott Wood, Linus Torvalds
The current 85xxCDS restart code fails to reset the PCI bus which can lead to odd behavior after the restart. This patch uses the VIA Super Southbridge to perform a PCI reset which will reset the entire system. NOTE: Since the VIA chip is behind a PCI-to-PCI bridge which can be disabled with a switch setting, it may not be possible to perform the PCI bus reset. In this case, the code defaults to the previous restart mechanism. Signed-off-by: Randy Vinson <redacted> --- arch/powerpc/platforms/85xx/mpc85xx_cds.c | 26 ++++++++++++++++++++++++++ 1 files changed, 26 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_cds.c b/arch/powerpc/platforms/85xx/mpc85xx_cds.c
index 431aaa2..f1eaf07 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_cds.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_cds.c@@ -62,6 +62,28 @@ static volatile u8 *cadmus; extern int mpc85xx_pci2_busno; +static void mpc85xx_cds_restart(char *cmd) +{ + struct pci_dev *dev; + u_char tmp; + + if ((dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686, + NULL))) { + + /* Use the VIA Super Southbridge to force a PCI reset */ + pci_read_config_byte(dev, 0x47, &tmp); + pci_write_config_byte(dev, 0x47, tmp | 1); + + pci_dev_put(dev); + } + + /* + * We should only get here if the P2P bridge is disabled. In that + * case, just use the default reset. + */ + mpc85xx_restart(NULL); +} + static int mpc85xx_exclude_device(u_char bus, u_char devfn) { if (bus == 0 && PCI_SLOT(devfn) == 0)
@@ -327,7 +349,11 @@ define_machine(mpc85xx_cds) { .init_IRQ = mpc85xx_cds_pic_init, .show_cpuinfo = mpc85xx_cds_show_cpuinfo, .get_irq = mpic_get_irq, +#ifdef CONFIG_PCI + .restart = mpc85xx_cds_restart, +#else .restart = mpc85xx_restart, +#endif .calibrate_decr = generic_calibrate_decr, .progress = udbg_progress, };
--
1.5.0.GIT