/*
 * Copyright Altera Corporation (C) 2014-2015
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */
#include <common.h>
#include <errno.h>
#include <div64.h>
#include <watchdog.h>
#include <asm/arch/fpga_manager.h>
#include <asm/arch/sdram.h>
#include <asm/arch/system_manager.h>
#include <asm/io.h>

DECLARE_GLOBAL_DATA_PTR;

struct sdram_prot_rule {
        u32     sdram_start;    /* SDRAM start address */
        u32     sdram_end;      /* SDRAM end address */
        u32     rule;           /* SDRAM protection rule number: 0-19 */
        int     valid;          /* Rule valid or not? 1 - valid, 0 not*/

        u32     security;
        u32     portmask;
        u32     result;
        u32     lo_prot_id;
        u32     hi_prot_id;
};

static struct socfpga_system_manager *sysmgr_regs =
        (struct socfpga_system_manager *)SOCFPGA_SYSMGR_ADDRESS;
static struct socfpga_sdr_ctrl *sdr_ctrl =
        (struct socfpga_sdr_ctrl *)SDR_CTRLGRP_ADDRESS;

/**
 * get_errata_rows() - Up the number of DRAM rows to cover entire address space
 * @cfg:        SDRAM controller configuration data
 *
 * SDRAM Failure happens when accessing non-existent memory. Artificially
 * increase the number of rows so that the memory controller thinks it has
 * 4GB of RAM. This function returns such amount of rows.
 */
static int get_errata_rows(const struct socfpga_sdram_config *cfg)
{
        /* Define constant for 4G memory - used for SDRAM errata workaround */
#define MEMSIZE_4G      (4ULL * 1024ULL * 1024ULL * 1024ULL)
        const unsigned long long memsize = MEMSIZE_4G;
        const unsigned int cs =
                ((cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_CSBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_CSBITS_LSB) + 1;
        const unsigned int rows =
                (cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_ROWBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_ROWBITS_LSB;
        const unsigned int banks =
                (cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_BANKBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_BANKBITS_LSB;
        const unsigned int cols =
                (cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_COLBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_COLBITS_LSB;
        const unsigned int width = 8;

        unsigned long long newrows;
        int bits, inewrowslog2;

        debug("workaround rows - memsize %lld\n", memsize);
        debug("workaround rows - cs        %d\n", cs);
        debug("workaround rows - width     %d\n", width);
        debug("workaround rows - rows      %d\n", rows);
        debug("workaround rows - banks     %d\n", banks);
        debug("workaround rows - cols      %d\n", cols);

        newrows = lldiv(memsize, cs * (width / 8));
        debug("rows workaround - term1 %lld\n", newrows);

        newrows = lldiv(newrows, (1 << banks) * (1 << cols));
        debug("rows workaround - term2 %lld\n", newrows);

        /*
         * Compute the hamming weight - same as number of bits set.
         * Need to see if result is ordinal power of 2 before
         * attempting log2 of result.
         */
        bits = generic_hweight32(newrows);

        debug("rows workaround - bits %d\n", bits);

        if (bits != 1) {
                printf("SDRAM workaround failed, bits set %d\n", bits);
                return rows;
        }

        if (newrows > UINT_MAX) {
                printf("SDRAM workaround rangecheck failed, %lld\n", newrows);
                return rows;
        }

        inewrowslog2 = __ilog2(newrows);

        debug("rows workaround - ilog2 %d, %lld\n", inewrowslog2, newrows);

        if (inewrowslog2 == -1) {
                printf("SDRAM workaround failed, newrows %lld\n", newrows);
                return rows;
        }

        return inewrowslog2;
}

/* SDRAM protection rules vary from 0-19, a total of 20 rules. */
static void sdram_set_rule(struct sdram_prot_rule *prule)
{
        u32 lo_addr_bits;
        u32 hi_addr_bits;
        int ruleno = prule->rule;

        /* Select the rule */
        writel(ruleno, &sdr_ctrl->prot_rule_rdwr);

        /* Obtain the address bits */
        lo_addr_bits = prule->sdram_start >> 20ULL;
        hi_addr_bits = (prule->sdram_end - 1) >> 20ULL;

        debug("sdram set rule start %x, %d\n", lo_addr_bits,
              prule->sdram_start);
        debug("sdram set rule end   %x, %d\n", hi_addr_bits,
              prule->sdram_end);

        /* Set rule addresses */
        writel(lo_addr_bits | (hi_addr_bits << 12), &sdr_ctrl->prot_rule_addr);

        /* Set rule protection ids */
        writel(prule->lo_prot_id | (prule->hi_prot_id << 12),
               &sdr_ctrl->prot_rule_id);

        /* Set the rule data */
        writel(prule->security | (prule->valid << 2) |
               (prule->portmask << 3) | (prule->result << 13),
               &sdr_ctrl->prot_rule_data);

        /* write the rule */
        writel(ruleno | (1 << 5), &sdr_ctrl->prot_rule_rdwr);

        /* Set rule number to 0 by default */
        writel(0, &sdr_ctrl->prot_rule_rdwr);
}

static void sdram_get_rule(struct sdram_prot_rule *prule)
{
        u32 addr;
        u32 id;
        u32 data;
        int ruleno = prule->rule;

        /* Read the rule */
        writel(ruleno, &sdr_ctrl->prot_rule_rdwr);
        writel(ruleno | (1 << 6), &sdr_ctrl->prot_rule_rdwr);

        /* Get the addresses */
        addr = readl(&sdr_ctrl->prot_rule_addr);
        prule->sdram_start = (addr & 0xFFF) << 20;
        prule->sdram_end = ((addr >> 12) & 0xFFF) << 20;

        /* Get the configured protection IDs */
        id = readl(&sdr_ctrl->prot_rule_id);
        prule->lo_prot_id = id & 0xFFF;
        prule->hi_prot_id = (id >> 12) & 0xFFF;

        /* Get protection data */
        data = readl(&sdr_ctrl->prot_rule_data);

        prule->security = data & 0x3;
        prule->valid = (data >> 2) & 0x1;
        prule->portmask = (data >> 3) & 0x3FF;
        prule->result = (data >> 13) & 0x1;
}

static void
sdram_set_protection_config(const u32 sdram_start, const u32 sdram_end)
{
        struct sdram_prot_rule rule;
        int rules;

        /* Start with accepting all SDRAM transaction */
        writel(0x0, &sdr_ctrl->protport_default);

        /* Clear all protection rules for warm boot case */
        memset(&rule, 0, sizeof(rule));

        for (rules = 0; rules < 20; rules++) {
                rule.rule = rules;
                sdram_set_rule(&rule);
        }

        /* new rule: accept SDRAM */
        rule.sdram_start = sdram_start;
        rule.sdram_end = sdram_end;
        rule.lo_prot_id = 0x0;
        rule.hi_prot_id = 0xFFF;
        rule.portmask = 0x3FF;
        rule.security = 0x3;
        rule.result = 0;
        rule.valid = 1;
        rule.rule = 0;

        /* set new rule */
        sdram_set_rule(&rule);

        /* default rule: reject everything */
        writel(0x3ff, &sdr_ctrl->protport_default);
}

static void sdram_dump_protection_config(void)
{
        struct sdram_prot_rule rule;
        int rules;

        debug("SDRAM Prot rule, default %x\n",
              readl(&sdr_ctrl->protport_default));

        for (rules = 0; rules < 20; rules++) {
                rule.rule = rules;
                sdram_get_rule(&rule);
                debug("Rule %d, rules ...\n", rules);
                debug("    sdram start %x\n", rule.sdram_start);
                debug("    sdram end   %x\n", rule.sdram_end);
                debug("    low prot id %d, hi prot id %d\n",
                      rule.lo_prot_id,
                      rule.hi_prot_id);
                debug("    portmask %x\n", rule.portmask);
                debug("    security %d\n", rule.security);
                debug("    result %d\n", rule.result);
                debug("    valid %d\n", rule.valid);
        }
}

/**
 * sdram_write_verify() - write to register and verify the write.
 * @addr:       Register address
 * @val:        Value to be written and verified
 *
 * This function writes to a register, reads back the value and compares
 * the result with the written value to check if the data match.
 */
static unsigned sdram_write_verify(const u32 *addr, const u32 val)
{
        u32 rval;

        debug("   Write - Address 0x%p Data 0x%08x\n", addr, val);
        writel(val, addr);

        debug("   Read and verify...");
        rval = readl(addr);
        if (rval != val) {
                debug("FAIL - Address 0x%p Expected 0x%08x Data 0x%08x\n",
                      addr, val, rval);
                return -EINVAL;
        }

        debug("correct!\n");
        return 0;
}

/**
 * sdr_get_ctrlcfg() - Get the value of DRAM CTRLCFG register
 * @cfg:        SDRAM controller configuration data
 *
 * Return the value of DRAM CTRLCFG register.
 */
static u32 sdr_get_ctrlcfg(const struct socfpga_sdram_config *cfg)
{
        const u32 csbits =
                ((cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_CSBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_CSBITS_LSB) + 1;
        u32 addrorder =
                (cfg->ctrl_cfg & SDR_CTRLGRP_CTRLCFG_ADDRORDER_MASK) >>
                        SDR_CTRLGRP_CTRLCFG_ADDRORDER_LSB;

        u32 ctrl_cfg = cfg->ctrl_cfg;

        /*
         * SDRAM Failure When Accessing Non-Existent Memory
         * Set the addrorder field of the SDRAM control register
         * based on the CSBITs setting.
         */
        if (csbits == 1) {
                if (addrorder != 0)
                        debug("INFO: Changing address order to 0 (chip, row, bank, column)\n");
                addrorder = 0;
        } else if (csbits == 2) {
                if (addrorder != 2)
                        debug("INFO: Changing address order to 2 (row, chip, bank, column)\n");
                addrorder = 2;
        }

        ctrl_cfg &= ~SDR_CTRLGRP_CTRLCFG_ADDRORDER_MASK;
        ctrl_cfg |= addrorder << SDR_CTRLGRP_CTRLCFG_ADDRORDER_LSB;

        return ctrl_cfg;
}

/**
 * sdr_get_addr_rw() - Get the value of DRAM ADDRW register
 * @cfg:        SDRAM controller configuration data
 *
 * Return the value of DRAM ADDRW register.
 */
static u32 sdr_get_addr_rw(const struct socfpga_sdram_config *cfg)
{
        /*
         * SDRAM Failure When Accessing Non-Existent Memory
         * Set SDR_CTRLGRP_DRAMADDRW_CSBITS_LSB to
         * log2(number of chip select bits). Since there's only
         * 1 or 2 chip selects, log2(1) => 0, and log2(2) => 1,
         * which is the same as "chip selects" - 1.
         */
        const int rows = get_errata_rows(cfg);
        u32 dram_addrw = cfg->dram_addrw & ~SDR_CTRLGRP_DRAMADDRW_ROWBITS_MASK;

        return dram_addrw | (rows << SDR_CTRLGRP_DRAMADDRW_ROWBITS_LSB);
}

/**
 * sdr_load_regs() - Load SDRAM controller registers
 * @cfg:        SDRAM controller configuration data
 *
 * This function loads the register values into the SDRAM controller block.
 */
static void sdr_load_regs(const struct socfpga_sdram_config *cfg)
{
        const u32 ctrl_cfg = sdr_get_ctrlcfg(cfg);
        const u32 dram_addrw = sdr_get_addr_rw(cfg);

        debug("\nConfiguring CTRLCFG\n");
        writel(ctrl_cfg, &sdr_ctrl->ctrl_cfg);

        debug("Configuring DRAMTIMING1\n");
        writel(cfg->dram_timing1, &sdr_ctrl->dram_timing1);

        debug("Configuring DRAMTIMING2\n");
        writel(cfg->dram_timing2, &sdr_ctrl->dram_timing2);

        debug("Configuring DRAMTIMING3\n");
        writel(cfg->dram_timing3, &sdr_ctrl->dram_timing3);

        debug("Configuring DRAMTIMING4\n");
        writel(cfg->dram_timing4, &sdr_ctrl->dram_timing4);

        debug("Configuring LOWPWRTIMING\n");
        writel(cfg->lowpwr_timing, &sdr_ctrl->lowpwr_timing);

        debug("Configuring DRAMADDRW\n");
        writel(dram_addrw, &sdr_ctrl->dram_addrw);

        debug("Configuring DRAMIFWIDTH\n");
        writel(cfg->dram_if_width, &sdr_ctrl->dram_if_width);

        debug("Configuring DRAMDEVWIDTH\n");
        writel(cfg->dram_dev_width, &sdr_ctrl->dram_dev_width);

        debug("Configuring LOWPWREQ\n");
        writel(cfg->lowpwr_eq, &sdr_ctrl->lowpwr_eq);

        debug("Configuring DRAMINTR\n");
        writel(cfg->dram_intr, &sdr_ctrl->dram_intr);

        debug("Configuring STATICCFG\n");
        writel(cfg->static_cfg, &sdr_ctrl->static_cfg);

        debug("Configuring CTRLWIDTH\n");
        writel(cfg->ctrl_width, &sdr_ctrl->ctrl_width);

        debug("Configuring PORTCFG\n");
        writel(cfg->port_cfg, &sdr_ctrl->port_cfg);

        debug("Configuring FIFOCFG\n");
        writel(cfg->fifo_cfg, &sdr_ctrl->fifo_cfg);

        debug("Configuring MPPRIORITY\n");
        writel(cfg->mp_priority, &sdr_ctrl->mp_priority);

        debug("Configuring MPWEIGHT_MPWEIGHT_0\n");
        writel(cfg->mp_weight0, &sdr_ctrl->mp_weight0);
        writel(cfg->mp_weight1, &sdr_ctrl->mp_weight1);
        writel(cfg->mp_weight2, &sdr_ctrl->mp_weight2);
        writel(cfg->mp_weight3, &sdr_ctrl->mp_weight3);

        debug("Configuring MPPACING_MPPACING_0\n");
        writel(cfg->mp_pacing0, &sdr_ctrl->mp_pacing0);
        writel(cfg->mp_pacing1, &sdr_ctrl->mp_pacing1);
        writel(cfg->mp_pacing2, &sdr_ctrl->mp_pacing2);
        writel(cfg->mp_pacing3, &sdr_ctrl->mp_pacing3);

        debug("Configuring MPTHRESHOLDRST_MPTHRESHOLDRST_0\n");
        writel(cfg->mp_threshold0, &sdr_ctrl->mp_threshold0);
        writel(cfg->mp_threshold1, &sdr_ctrl->mp_threshold1);
        writel(cfg->mp_threshold2, &sdr_ctrl->mp_threshold2);

        debug("Configuring PHYCTRL_PHYCTRL_0\n");
        writel(cfg->phy_ctrl0, &sdr_ctrl->phy_ctrl0);

        debug("Configuring CPORTWIDTH\n");
        writel(cfg->cport_width, &sdr_ctrl->cport_width);

        debug("Configuring CPORTWMAP\n");
        writel(cfg->cport_wmap, &sdr_ctrl->cport_wmap);

        debug("Configuring CPORTRMAP\n");
        writel(cfg->cport_rmap, &sdr_ctrl->cport_rmap);

        debug("Configuring RFIFOCMAP\n");
        writel(cfg->rfifo_cmap, &sdr_ctrl->rfifo_cmap);

        debug("Configuring WFIFOCMAP\n");
        writel(cfg->wfifo_cmap, &sdr_ctrl->wfifo_cmap);

        debug("Configuring CPORTRDWR\n");
        writel(cfg->cport_rdwr, &sdr_ctrl->cport_rdwr);

        debug("Configuring DRAMODT\n");
        writel(cfg->dram_odt, &sdr_ctrl->dram_odt);

        debug("Configuring EXTRATIME1\n");
        writel(cfg->extratime1, &sdr_ctrl->extratime1);
}

/**
 * sdram_mmr_init_full() - Function to initialize SDRAM MMR
 * @sdr_phy_reg:        Value of the PHY control register 0
 *
 * Initialize the SDRAM MMR.
 */
int sdram_mmr_init_full(unsigned int sdr_phy_reg)
{
        const struct socfpga_sdram_config *cfg = socfpga_get_sdram_config();
        const unsigned int rows =
                (cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_ROWBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_ROWBITS_LSB;
        int ret;

        writel(rows, &sysmgr_regs->iswgrp_handoff[4]);

        sdr_load_regs(cfg);

        /* saving this value to SYSMGR.ISWGRP.HANDOFF.FPGA2SDR */
        writel(cfg->fpgaport_rst, &sysmgr_regs->iswgrp_handoff[3]);

        /* only enable if the FPGA is programmed */
        if (fpgamgr_test_fpga_ready()) {
                ret = sdram_write_verify(&sdr_ctrl->fpgaport_rst,
                                         cfg->fpgaport_rst);
                if (ret)
                        return ret;
        }

        /* Restore the SDR PHY Register if valid */
        if (sdr_phy_reg != 0xffffffff)
                writel(sdr_phy_reg, &sdr_ctrl->phy_ctrl0);

        /* Final step - apply configuration changes */
        debug("Configuring STATICCFG\n");
        clrsetbits_le32(&sdr_ctrl->static_cfg,
                        SDR_CTRLGRP_STATICCFG_APPLYCFG_MASK,
                        1 << SDR_CTRLGRP_STATICCFG_APPLYCFG_LSB);

        sdram_set_protection_config(0, sdram_calculate_size() - 1);

        sdram_dump_protection_config();

        return 0;
}

/**
 * sdram_calculate_size() - Calculate SDRAM size
 *
 * Calculate SDRAM device size based on SDRAM controller parameters.
 * Size is specified in bytes.
 */
unsigned long sdram_calculate_size(void)
{
        unsigned long temp;
        unsigned long row, bank, col, cs, width;
        const struct socfpga_sdram_config *cfg = socfpga_get_sdram_config();
        const unsigned int csbits =
                ((cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_CSBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_CSBITS_LSB) + 1;
        const unsigned int rowbits =
                (cfg->dram_addrw & SDR_CTRLGRP_DRAMADDRW_ROWBITS_MASK) >>
                        SDR_CTRLGRP_DRAMADDRW_ROWBITS_LSB;

        temp = readl(&sdr_ctrl->dram_addrw);
        col = (temp & SDR_CTRLGRP_DRAMADDRW_COLBITS_MASK) >>
                SDR_CTRLGRP_DRAMADDRW_COLBITS_LSB;

        /*
         * SDRAM Failure When Accessing Non-Existent Memory
         * Use ROWBITS from Quartus/QSys to calculate SDRAM size
         * since the FB specifies we modify ROWBITs to work around SDRAM
         * controller issue.
         */
        row = readl(&sysmgr_regs->iswgrp_handoff[4]);
        if (row == 0)
                row = rowbits;
        /*
         * If the stored handoff value for rows is greater than
         * the field width in the sdr.dramaddrw register then
         * something is very wrong. Revert to using the the #define
         * value handed off by the SOCEDS tool chain instead of
         * using a broken value.
         */
        if (row > 31)
                row = rowbits;

        bank = (temp & SDR_CTRLGRP_DRAMADDRW_BANKBITS_MASK) >>
                SDR_CTRLGRP_DRAMADDRW_BANKBITS_LSB;

        /*
         * SDRAM Failure When Accessing Non-Existent Memory
         * Use CSBITs from Quartus/QSys to calculate SDRAM size
         * since the FB specifies we modify CSBITs to work around SDRAM
         * controller issue.
         */
        cs = csbits;

        width = readl(&sdr_ctrl->dram_if_width);

        /* ECC would not be calculated as its not addressible */
        if (width == SDRAM_WIDTH_32BIT_WITH_ECC)
                width = 32;
        if (width == SDRAM_WIDTH_16BIT_WITH_ECC)
                width = 16;

        /* calculate the SDRAM size base on this info */
        temp = 1 << (row + bank + col);
        temp = temp * cs * (width  / 8);

        debug("%s returns %ld\n", __func__, temp);

        return temp;
}