[v2,14/21] mmc: dwmmc: socfpga: Secure register access in MMC driver

From: Chee Hong Ang <chee.hong.ang at intel.com>

Allow MMC driver to access System Manager's SDMMC control
register in non-secure mode (EL2).

Signed-off-by: Chee Hong Ang <chee.hong.ang at intel.com>
---
 drivers/mmc/socfpga_dw_mmc.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

> From: Chee Hong Ang <chee.hong.ang at intel.com>
> 
> Allow MMC driver to access System Manager's SDMMC control register in non-
> secure mode (EL2).
> 
> Signed-off-by: Chee Hong Ang <chee.hong.ang at intel.com>
> ---
>  drivers/mmc/socfpga_dw_mmc.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/socfpga_dw_mmc.c
> b/drivers/mmc/socfpga_dw_mmc.c index 786cdc7..558f246 100644
> --- a/drivers/mmc/socfpga_dw_mmc.c
> +++ b/drivers/mmc/socfpga_dw_mmc.c
> @@ -5,6 +5,7 @@
> 
>  #include <common.h>
>  #include <asm/arch/clock_manager.h>
> +#include <asm/arch/secure_reg_helper.h>
>  #include <asm/arch/system_manager.h>
>  #include <clk.h>
>  #include <dm.h>
> @@ -57,10 +58,12 @@ static void socfpga_dwmci_clksel(struct dwmci_host
> *host)
> 
>  	debug("%s: drvsel %d smplsel %d\n", __func__,
>  	      priv->drvsel, priv->smplsel);
> -	writel(sdmmc_mask, socfpga_get_sysmgr_addr() + SYSMGR_SDMMC);
> +	socfpga_secure_reg_write32(sdmmc_mask, socfpga_get_sysmgr_addr()
> +
> +				   SYSMGR_SDMMC);
> 
>  	debug("%s: SYSMGR_SDMMCGRP_CTRL_REG = 0x%x\n", __func__,
> -		readl(socfpga_get_sysmgr_addr() + SYSMGR_SDMMC));
> +	      socfpga_secure_reg_read32(socfpga_get_sysmgr_addr() +
> +	      SYSMGR_SDMMC));
> 
>  	/* Enable SDMMC clock */
>  	setbits_le32(socfpga_get_clkmgr_addr() + CLKMGR_PERPLL_EN,
> --
> 2.7.4
This SDMMC driver need to access System Manager's SDMMC control register
(secure zone) to configure the clock's phase shift settings. I don't think this
could be separated from the driver. I will add/define a high-level API in ATF
to be used by this SDMMC driver from non-secure world (EL2).
This high-level API (SMC/PSCI calls) will be properly documented in
'include/linux/intel-smc.h'