diff options
| -rw-r--r-- | cpu/mpc85xx/pci.c | 3 | ||||
| -rw-r--r-- | doc/README.mpc85xxads | 3 | ||||
| -rw-r--r-- | include/configs/MPC8540ADS.h | 6 |
3 files changed, 11 insertions, 1 deletions
diff --git a/cpu/mpc85xx/pci.c b/cpu/mpc85xx/pci.c index ca11bce22e..cfb7dcdc89 100644 --- a/cpu/mpc85xx/pci.c +++ b/cpu/mpc85xx/pci.c @@ -72,6 +72,9 @@ pci_mpc85xx_init(struct pci_controller *board_hose) if (!(gur->pordevsr & PORDEVSR_PCI)) { /* PCI-X init */ + if (CONFIG_SYS_CLK_FREQ < 66000000) + printf("PCI-X will only work at 66 MHz\n"); + reg16 = PCI_X_CMD_MAX_SPLIT | PCI_X_CMD_MAX_READ | PCI_X_CMD_ERO | PCI_X_CMD_DPERR_E; pci_hose_write_config_word(hose, dev, PCIX_COMMAND, reg16); diff --git a/doc/README.mpc85xxads b/doc/README.mpc85xxads index f0cf782a8f..ae8202bdd1 100644 --- a/doc/README.mpc85xxads +++ b/doc/README.mpc85xxads @@ -100,6 +100,9 @@ Updated 13-July-2004 Jon Loeliger SW7[1:4] = 0101 = 5 => 5 x 66 = 330 CCB Sysclk SW7[5:6] = 01 => 5:2 x 330 = 825 Core clock + In order to use PCI-X (only in the first PCI slot. The one with + the RIO connector), you need to set SW1[4] (config) to 1 (off). + Also, configure the board to run PCI at 66 MHz. 2. MEMORY MAP TO WORK WITH LINUX KERNEL diff --git a/include/configs/MPC8540ADS.h b/include/configs/MPC8540ADS.h index 81ee945d49..8e4d2c95a4 100644 --- a/include/configs/MPC8540ADS.h +++ b/include/configs/MPC8540ADS.h @@ -68,10 +68,14 @@ * The board, however, can run at 66MHz. In any event, this value * must match the settings of some switches. Details can be found * in the README.mpc85xxads. + * + * XXX -- Can't we run at 66 MHz, anyway? PCI should drop to + * 33MHz to accommodate, based on a PCI pin. + * Note that PCI-X won't work at 33MHz. */ #ifndef CONFIG_SYS_CLK_FREQ -#define CONFIG_SYS_CLK_FREQ 66000000 +#define CONFIG_SYS_CLK_FREQ 33000000 #endif |