Performs pinmux and gpio handling for switching to PCI mode on EVMs with workaround as described on http://wiki.davincidsp.com/index.php/Pinmux_Switching_from_NAND_to_PCI. Skips setting pinmux if already set (e.g., by hardware).
Signed-off-by: Hemant Pedanekar <[email protected]> --- arch/arm/mach-davinci/board-dm646x-evm.c | 79 +++++++++++++++++++++++++++++- 1 files changed, 78 insertions(+), 1 deletions(-) diff --git a/arch/arm/mach-davinci/board-dm646x-evm.c b/arch/arm/mach-davinci/board-dm646x-evm.c index b1bf18c..e5ba479 100644 --- a/arch/arm/mach-davinci/board-dm646x-evm.c +++ b/arch/arm/mach-davinci/board-dm646x-evm.c @@ -42,6 +42,7 @@ #include <mach/dm646x.h> #include <mach/common.h> +#include <mach/mux.h> #include <mach/psc.h> #include <mach/serial.h> #include <mach/i2c.h> @@ -49,6 +50,19 @@ #include <mach/emac.h> #include <mach/common.h> +#if defined(CONFIG_PCI) +#define HAS_PCI 1 +#else +#define HAS_PCI 0 +#endif + +#if defined(CONFIG_MTD_NAND_DAVINCI) || \ + defined(CONFIG_MTD_NAND_DAVINCI_MODULE) +#define HAS_NAND 1 +#else +#define HAS_NAND 0 +#endif + #if defined(CONFIG_BLK_DEV_PALMCHIP_BK3710) || \ defined(CONFIG_BLK_DEV_PALMCHIP_BK3710_MODULE) #define HAS_ATA 1 @@ -67,6 +81,58 @@ static struct davinci_uart_config uart_config __initdata = { .enabled_uarts = (1 << 0), }; +/* Setup DM6467 for PCI mode. In case of default EVM, the CPLD along with FET + * switches takes care of switching to PCI Boot mode when the EVM is put in + * the PCI slot and this funtion needs to do nothing. While in case when the + * CPLD code/ Hardware is reworked (not to do autoswitch), the code below + * handles mux configurations to switch to PCI (Host) mode and takes care of + * driving RST# over PCI Bus. + * + * Note: This function relies on h/w setting of PCIEN to distinguish between + * modified and unmodified EVM and might not work in case s/w (e.g., bootloader) + * is manipulating PCIEN after booting. + */ +static void dm646xevm_pci_setup(void) +{ + void __iomem *base = IO_ADDRESS(DAVINCI_SYSTEM_MODULE_BASE); + + /* Skip this if PCIEN is already set in PINMUX0 */ + if (!((__raw_readl(base + PINMUX0)) & (1<<2))) { + /* Power up the I/O cells for PCI interface */ + __raw_writel(__raw_readl(base + DM64XX_VDD3P3V_PWDN) + & ~(3<<16), base + DM64XX_VDD3P3V_PWDN); + + davinci_cfg_reg(DM646X_HPI32EN); + + /* Drive GPIO[13] High to avoid reset when PCI is + * enabled + */ + if (gpio_request(13, "RST#") != 0) { + pr_err("Request for GPIO13 failed.\n"); + return; + } + + gpio_direction_output(13, 1); + + /* Ensure AUDCK1 is disabled to control GPIO[2] */ + davinci_cfg_reg(DM646X_AUDCK1); + + davinci_cfg_reg(DM646X_PCIEN); + + /* Drive GPIO[2] high to take the PCI bus out of reset + * (drive RST#) and select B2 of the FET mux on EVM to + * deselect NAND and switch to PCI Bus + */ + if (gpio_request(2, "PCIRST#") != 0) { + pr_err("Request for GPIO2 failed.\n"); + return; + } + gpio_direction_output(2, 1); + } else { + pr_info("PCI_EN is already asserted.\n"); + } +} + /* CPLD Register 0 Client: used for I/O Control */ static int cpld_reg0_probe(struct i2c_client *client, const struct i2c_device_id *id) @@ -328,8 +394,19 @@ static __init void evm_init(void) dm646x_init_mcasp0(&dm646x_evm_snd_data[0]); dm646x_init_mcasp1(&dm646x_evm_snd_data[1]); - if (HAS_ATA) + if (HAS_PCI) { + if (HAS_ATA) + pr_warning("WARNING: both PCI and IDE are " + "enabled, but they share some pins.\n" + "\tDisable PCI for IDE support.\n"); + else if (HAS_NAND) + pr_warning("WARNING: both PCI and NAND are " + "enabled, but they share AEMIF pins.\n" + "\tDisable PCI for NAND support.\n"); + dm646xevm_pci_setup(); + } else if (HAS_ATA) { dm646x_init_ide(); + } soc_info->emac_pdata->phy_mask = DM646X_EVM_PHY_MASK; soc_info->emac_pdata->mdio_max_freq = DM646X_EVM_MDIO_FREQUENCY; -- 1.6.2.4 _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
