// SPDX-License-Identifier: GPL-2.0
/*
 * Linux driver for digital TV devices equipped with B2C2 FlexcopII(b)/III
 * flexcop-dma.c - configuring and controlling the DMA of the FlexCop
 * see flexcop.c for copyright information
 */
#include "flexcop.h"

int flexcop_dma_allocate(struct pci_dev *pdev,
                struct flexcop_dma *dma, u32 size)
{
        u8 *tcpu;
        dma_addr_t tdma = 0;

        if (size % 2) {
                err("dma buffersize has to be even.");
                return -EINVAL;
        }

        tcpu = dma_alloc_coherent(&pdev->dev, size, &tdma, GFP_KERNEL);
        if (tcpu != NULL) {
                dma->pdev = pdev;
                dma->cpu_addr0 = tcpu;
                dma->dma_addr0 = tdma;
                dma->cpu_addr1 = tcpu + size/2;
                dma->dma_addr1 = tdma + size/2;
                dma->size = size/2;
                return 0;
        }
        return -ENOMEM;
}
EXPORT_SYMBOL(flexcop_dma_allocate);

void flexcop_dma_free(struct flexcop_dma *dma)
{
        dma_free_coherent(&dma->pdev->dev, dma->size * 2, dma->cpu_addr0,
                          dma->dma_addr0);
        memset(dma, 0, sizeof(struct flexcop_dma));
}
EXPORT_SYMBOL(flexcop_dma_free);

int flexcop_dma_config(struct flexcop_device *fc,
                struct flexcop_dma *dma,
                flexcop_dma_index_t dma_idx)
{
        flexcop_ibi_value v0x0, v0x4, v0xc;

        v0x0.raw = v0x4.raw = v0xc.raw = 0;
        v0x0.dma_0x0.dma_address0 = dma->dma_addr0 >> 2;
        v0xc.dma_0xc.dma_address1 = dma->dma_addr1 >> 2;
        v0x4.dma_0x4_write.dma_addr_size = dma->size / 4;

        if ((dma_idx & FC_DMA_1) == dma_idx) {
                fc->write_ibi_reg(fc, dma1_000, v0x0);
                fc->write_ibi_reg(fc, dma1_004, v0x4);
                fc->write_ibi_reg(fc, dma1_00c, v0xc);
        } else if ((dma_idx & FC_DMA_2) == dma_idx) {
                fc->write_ibi_reg(fc, dma2_010, v0x0);
                fc->write_ibi_reg(fc, dma2_014, v0x4);
                fc->write_ibi_reg(fc, dma2_01c, v0xc);
        } else {
                err("either DMA1 or DMA2 can be configured within one %s call.",
                        __func__);
                return -EINVAL;
        }

        return 0;
}
EXPORT_SYMBOL(flexcop_dma_config);

/* start the DMA transfers, but not the DMA IRQs */
int flexcop_dma_xfer_control(struct flexcop_device *fc,
                flexcop_dma_index_t dma_idx,
                flexcop_dma_addr_index_t index,
                int onoff)
{
        flexcop_ibi_value v0x0, v0xc;
        flexcop_ibi_register r0x0, r0xc;

        if ((dma_idx & FC_DMA_1) == dma_idx) {
                r0x0 = dma1_000;
                r0xc = dma1_00c;
        } else if ((dma_idx & FC_DMA_2) == dma_idx) {
                r0x0 = dma2_010;
                r0xc = dma2_01c;
        } else {
                err("transfer DMA1 or DMA2 can be started within one %s call.",
                        __func__);
                return -EINVAL;
        }

        v0x0 = fc->read_ibi_reg(fc, r0x0);
        v0xc = fc->read_ibi_reg(fc, r0xc);

        deb_rdump("reg: %03x: %x\n", r0x0, v0x0.raw);
        deb_rdump("reg: %03x: %x\n", r0xc, v0xc.raw);

        if (index & FC_DMA_SUBADDR_0)
                v0x0.dma_0x0.dma_0start = onoff;

        if (index & FC_DMA_SUBADDR_1)
                v0xc.dma_0xc.dma_1start = onoff;

        fc->write_ibi_reg(fc, r0x0, v0x0);
        fc->write_ibi_reg(fc, r0xc, v0xc);

        deb_rdump("reg: %03x: %x\n", r0x0, v0x0.raw);
        deb_rdump("reg: %03x: %x\n", r0xc, v0xc.raw);
        return 0;
}
EXPORT_SYMBOL(flexcop_dma_xfer_control);

static int flexcop_dma_remap(struct flexcop_device *fc,
                flexcop_dma_index_t dma_idx,
                int onoff)
{
        flexcop_ibi_register r = (dma_idx & FC_DMA_1) ? dma1_00c : dma2_01c;
        flexcop_ibi_value v = fc->read_ibi_reg(fc, r);

        deb_info("%s\n", __func__);
        v.dma_0xc.remap_enable = onoff;
        fc->write_ibi_reg(fc, r, v);
        return 0;
}

int flexcop_dma_control_timer_irq(struct flexcop_device *fc,
                flexcop_dma_index_t no,
                int onoff)
{
        flexcop_ibi_value v = fc->read_ibi_reg(fc, ctrl_208);

        if (no & FC_DMA_1)
                v.ctrl_208.DMA1_Timer_Enable_sig = onoff;

        if (no & FC_DMA_2)
                v.ctrl_208.DMA2_Timer_Enable_sig = onoff;

        fc->write_ibi_reg(fc, ctrl_208, v);
        return 0;
}
EXPORT_SYMBOL(flexcop_dma_control_timer_irq);

/* 1 cycles = 1.97 msec */
int flexcop_dma_config_timer(struct flexcop_device *fc,
                flexcop_dma_index_t dma_idx, u8 cycles)
{
        flexcop_ibi_register r = (dma_idx & FC_DMA_1) ? dma1_004 : dma2_014;
        flexcop_ibi_value v = fc->read_ibi_reg(fc, r);

        flexcop_dma_remap(fc, dma_idx, 0);

        deb_info("%s\n", __func__);
        v.dma_0x4_write.dmatimer = cycles;
        fc->write_ibi_reg(fc, r, v);
        return 0;
}
EXPORT_SYMBOL(flexcop_dma_config_timer);