drivers/gpio/mvmfp.c

   1 /*
   2  * (C) Copyright 2010
   3  * Marvell Semiconductor <www.marvell.com>
   4  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>,
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <common.h>
  10 #include <asm/io.h>
  11 #include <mvmfp.h>
  12 #include <asm/arch/mfp.h>
  13
  14 /*
  15  * mfp_config
  16  *
  17  * On most of Marvell SoCs (ex. ARMADA100) there is Multi-Funtion-Pin
  18  * configuration registers to configure each GPIO/Function pin on the
  19  * SoC.
  20  *
  21  * This function reads the array of values for
  22  * MFPR_X registers and programms them into respective
  23  * Multi-Function Pin registers.
  24  * It supports - Alternate Function Selection programming.
  25  *
  26  * Whereas,
  27  * The Configureation value is constructed using MFP()
  28  * array consists of 32bit values as defined in MFP(xx,xx..) macro
  29  */
  30 void mfp_config(u32 *mfp_cfgs)
  31 {
  32         u32 *p_mfpr = NULL;
  33         u32 cfg_val, val;
  34
  35         do {
  36                 cfg_val = *mfp_cfgs++;
  37                 /* exit if End of configuration table detected */
  38                 if (cfg_val == MFP_EOC)
  39                         break;
  40
  41                 p_mfpr = (u32 *)(MV_MFPR_BASE
  42                                 + MFP_REG_GET_OFFSET(cfg_val));
  43
  44                 /* Write a mfg register as per configuration */
  45                 val = 0;
  46                 if (cfg_val & MFP_AF_FLAG)
  47                         /* Abstract and program Afternate-Func Selection */
  48                         val |= cfg_val & MFP_AF_MASK;
  49                 if (cfg_val & MFP_EDGE_FLAG)
  50                         /* Abstract and program Edge configuration */
  51                         val |= cfg_val & MFP_LPM_EDGE_MASK;
  52                 if (cfg_val & MFP_DRIVE_FLAG)
  53                         /* Abstract and program Drive configuration */
  54                         val |= cfg_val & MFP_DRIVE_MASK;
  55                 if (cfg_val & MFP_PULL_FLAG)
  56                         /* Abstract and program Pullup/down configuration */
  57                         val |= cfg_val & MFP_PULL_MASK;
  58
  59                 writel(val, p_mfpr);
  60         } while (1);
  61         /*
  62          * perform a read-back of any MFPR register to make sure the
  63          * previous writings are finished
  64          */
  65         readl(p_mfpr);
  66 }