X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=drivers%2Fspi%2Frk_spi.c;h=833cb04922ebb97e6d2dc74549c28ac23370de74;hb=c05ed00afb95fa5237f16962fccf5810437317bf;hp=3e44f1795e3ccbcfedb606ece22b01bebd07fde5;hpb=e1a71f8b339220fa74c9cd5d36ae9c444c492e83;p=oweals%2Fu-boot.git diff --git a/drivers/spi/rk_spi.c b/drivers/spi/rk_spi.c index 3e44f1795e..833cb04922 100644 --- a/drivers/spi/rk_spi.c +++ b/drivers/spi/rk_spi.c @@ -1,12 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0+ /* * spi driver for rockchip * + * (C) 2019 Theobroma Systems Design und Consulting GmbH + * * (C) Copyright 2015 Google, Inc * * (C) Copyright 2008-2013 Rockchip Electronics * Peter, Software Engineering, . - * - * SPDX-License-Identifier: GPL-2.0+ */ #include @@ -14,19 +15,31 @@ #include #include #include +#include #include +#include +#include #include #include -#include -#include +#include +#include #include #include "rk_spi.h" -DECLARE_GLOBAL_DATA_PTR; - /* Change to 1 to output registers at the start of each transaction */ #define DEBUG_RK_SPI 0 +/* + * ctrlr1 is 16-bits, so we should support lengths of 0xffff + 1. However, + * the controller seems to hang when given 0x10000, so stick with this for now. + */ +#define ROCKCHIP_SPI_MAX_TRANLEN 0xffff + +struct rockchip_spi_params { + /* RXFIFO overruns and TXFIFO underruns stop the master clock */ + bool master_manages_fifo; +}; + struct rockchip_spi_platdata { #if CONFIG_IS_ENABLED(OF_PLATDATA) struct dtd_rockchip_rk3288_spi of_plat; @@ -43,11 +56,8 @@ struct rockchip_spi_priv { unsigned int max_freq; unsigned int mode; ulong last_transaction_us; /* Time of last transaction end */ - u8 bits_per_word; /* max 16 bits per word */ - u8 n_bytes; unsigned int speed_hz; unsigned int last_speed_hz; - unsigned int tmode; uint input_rate; }; @@ -79,12 +89,31 @@ static void rkspi_enable_chip(struct rockchip_spi *regs, bool enable) static void rkspi_set_clk(struct rockchip_spi_priv *priv, uint speed) { - uint clk_div; + /* + * We should try not to exceed the speed requested by the caller: + * when selecting a divider, we need to make sure we round up. + */ + uint clk_div = DIV_ROUND_UP(priv->input_rate, speed); + + /* The baudrate register (BAUDR) is defined as a 32bit register where + * the upper 16bit are reserved and having 'Fsclk_out' in the lower + * 16bits with 'Fsclk_out' defined as follows: + * + * Fsclk_out = Fspi_clk/ SCKDV + * Where SCKDV is any even value between 2 and 65534. + */ + if (clk_div > 0xfffe) { + clk_div = 0xfffe; + debug("%s: can't divide down to %d Hz (actual will be %d Hz)\n", + __func__, speed, priv->input_rate / clk_div); + } + + /* Round up to the next even 16bit number */ + clk_div = (clk_div + 1) & 0xfffe; - clk_div = clk_get_divisor(priv->input_rate, speed); debug("spi speed %u, div %u\n", speed, clk_div); - writel(clk_div, &priv->regs->baudr); + clrsetbits_le32(&priv->regs->baudr, 0xffff, clk_div); priv->last_speed_hz = speed; } @@ -114,8 +143,13 @@ static void spi_cs_activate(struct udevice *dev, uint cs) if (plat->deactivate_delay_us && priv->last_transaction_us) { ulong delay_us; /* The delay completed so far */ delay_us = timer_get_us() - priv->last_transaction_us; - if (delay_us < plat->deactivate_delay_us) - udelay(plat->deactivate_delay_us - delay_us); + if (delay_us < plat->deactivate_delay_us) { + ulong additional_delay_us = + plat->deactivate_delay_us - delay_us; + debug("%s: delaying by %ld us\n", + __func__, additional_delay_us); + udelay(additional_delay_us); + } } debug("activate cs%u\n", cs); @@ -163,11 +197,9 @@ static int rockchip_spi_ofdata_to_platdata(struct udevice *bus) #if !CONFIG_IS_ENABLED(OF_PLATDATA) struct rockchip_spi_platdata *plat = dev_get_platdata(bus); struct rockchip_spi_priv *priv = dev_get_priv(bus); - const void *blob = gd->fdt_blob; - int node = dev_of_offset(bus); int ret; - plat->base = dev_get_addr(bus); + plat->base = dev_read_addr(bus); ret = clk_get_by_index(bus, 0, &priv->clk); if (ret < 0) { @@ -176,12 +208,13 @@ static int rockchip_spi_ofdata_to_platdata(struct udevice *bus) return ret; } - plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency", - 50000000); - plat->deactivate_delay_us = fdtdec_get_int(blob, node, - "spi-deactivate-delay", 0); - plat->activate_delay_us = fdtdec_get_int(blob, node, - "spi-activate-delay", 0); + plat->frequency = + dev_read_u32_default(bus, "spi-max-frequency", 50000000); + plat->deactivate_delay_us = + dev_read_u32_default(bus, "spi-deactivate-delay", 0); + plat->activate_delay_us = + dev_read_u32_default(bus, "spi-activate-delay", 0); + debug("%s: base=%x, max-frequency=%d, deactivate_delay=%d\n", __func__, (uint)plat->base, plat->frequency, plat->deactivate_delay_us); @@ -190,6 +223,34 @@ static int rockchip_spi_ofdata_to_platdata(struct udevice *bus) return 0; } +static int rockchip_spi_calc_modclk(ulong max_freq) +{ + /* + * While this is not strictly correct for the RK3368, as the + * GPLL will be 576MHz, things will still work, as the + * clk_set_rate(...) implementation in our clock-driver will + * chose the next closest rate not exceeding what we request + * based on the output of this function. + */ + + unsigned div; + const unsigned long gpll_hz = 594000000UL; + + /* + * We need to find an input clock that provides at least twice + * the maximum frequency and can be generated from the assumed + * speed of GPLL (594MHz) using an integer divider. + * + * To give us more achievable bitrates at higher speeds (these + * are generated by dividing by an even 16-bit integer from + * this frequency), we try to have an input frequency of at + * least 4x our max_freq. + */ + + div = DIV_ROUND_UP(gpll_hz, max_freq * 4); + return gpll_hz / div; +} + static int rockchip_spi_probe(struct udevice *bus) { struct rockchip_spi_platdata *plat = dev_get_platdata(bus); @@ -207,19 +268,19 @@ static int rockchip_spi_probe(struct udevice *bus) priv->last_transaction_us = timer_get_us(); priv->max_freq = plat->frequency; - /* - * Use 99 MHz as our clock since it divides nicely into 594 MHz which - * is the assumed speed for CLK_GENERAL. - */ - ret = clk_set_rate(&priv->clk, 99000000); + /* Clamp the value from the DTS against any hardware limits */ + if (priv->max_freq > ROCKCHIP_SPI_MAX_RATE) + priv->max_freq = ROCKCHIP_SPI_MAX_RATE; + + /* Find a module-input clock that fits with the max_freq setting */ + ret = clk_set_rate(&priv->clk, + rockchip_spi_calc_modclk(priv->max_freq)); if (ret < 0) { debug("%s: Failed to set clock: %d\n", __func__, ret); return ret; } priv->input_rate = ret; debug("%s: rate = %u\n", __func__, priv->input_rate); - priv->bits_per_word = 8; - priv->tmode = TMOD_TR; /* Tx & Rx */ return 0; } @@ -229,28 +290,10 @@ static int rockchip_spi_claim_bus(struct udevice *dev) struct udevice *bus = dev->parent; struct rockchip_spi_priv *priv = dev_get_priv(bus); struct rockchip_spi *regs = priv->regs; - u8 spi_dfs, spi_tf; uint ctrlr0; /* Disable the SPI hardware */ - rkspi_enable_chip(regs, 0); - - switch (priv->bits_per_word) { - case 8: - priv->n_bytes = 1; - spi_dfs = DFS_8BIT; - spi_tf = HALF_WORD_OFF; - break; - case 16: - priv->n_bytes = 2; - spi_dfs = DFS_16BIT; - spi_tf = HALF_WORD_ON; - break; - default: - debug("%s: unsupported bits: %dbits\n", __func__, - priv->bits_per_word); - return -EPROTONOSUPPORT; - } + rkspi_enable_chip(regs, false); if (priv->speed_hz != priv->last_speed_hz) rkspi_set_clk(priv, priv->speed_hz); @@ -259,7 +302,7 @@ static int rockchip_spi_claim_bus(struct udevice *dev) ctrlr0 = OMOD_MASTER << OMOD_SHIFT; /* Data Frame Size */ - ctrlr0 |= spi_dfs << DFS_SHIFT; + ctrlr0 |= DFS_8BIT << DFS_SHIFT; /* set SPI mode 0..3 */ if (priv->mode & SPI_CPOL) @@ -280,7 +323,7 @@ static int rockchip_spi_claim_bus(struct udevice *dev) ctrlr0 |= FBM_MSB << FBM_SHIFT; /* Byte and Halfword Transform */ - ctrlr0 |= spi_tf << HALF_WORD_TX_SHIFT; + ctrlr0 |= HALF_WORD_OFF << HALF_WORD_TX_SHIFT; /* Rxd Sample Delay */ ctrlr0 |= 0 << RXDSD_SHIFT; @@ -289,7 +332,7 @@ static int rockchip_spi_claim_bus(struct udevice *dev) ctrlr0 |= FRF_SPI << FRF_SHIFT; /* Tx and Rx mode */ - ctrlr0 |= (priv->tmode & TMOD_MASK) << TMOD_SHIFT; + ctrlr0 |= TMOD_TR << TMOD_SHIFT; writel(ctrlr0, ®s->ctrlr0); @@ -306,6 +349,83 @@ static int rockchip_spi_release_bus(struct udevice *dev) return 0; } +static inline int rockchip_spi_16bit_reader(struct udevice *dev, + u8 **din, int *len) +{ + struct udevice *bus = dev->parent; + const struct rockchip_spi_params * const data = + (void *)dev_get_driver_data(bus); + struct rockchip_spi_priv *priv = dev_get_priv(bus); + struct rockchip_spi *regs = priv->regs; + const u32 saved_ctrlr0 = readl(®s->ctrlr0); +#if defined(DEBUG) + u32 statistics_rxlevels[33] = { }; +#endif + u32 frames = *len / 2; + u8 *in = (u8 *)(*din); + u32 max_chunk_size = SPI_FIFO_DEPTH; + + if (!frames) + return 0; + + /* + * If we know that the hardware will manage RXFIFO overruns + * (i.e. stop the SPI clock until there's space in the FIFO), + * we the allow largest possible chunk size that can be + * represented in CTRLR1. + */ + if (data && data->master_manages_fifo) + max_chunk_size = ROCKCHIP_SPI_MAX_TRANLEN; + + // rockchip_spi_configure(dev, mode, size) + rkspi_enable_chip(regs, false); + clrsetbits_le32(®s->ctrlr0, + TMOD_MASK << TMOD_SHIFT, + TMOD_RO << TMOD_SHIFT); + /* 16bit data frame size */ + clrsetbits_le32(®s->ctrlr0, DFS_MASK, DFS_16BIT); + + /* Update caller's context */ + const u32 bytes_to_process = 2 * frames; + *din += bytes_to_process; + *len -= bytes_to_process; + + /* Process our frames */ + while (frames) { + u32 chunk_size = min(frames, max_chunk_size); + + frames -= chunk_size; + + writew(chunk_size - 1, ®s->ctrlr1); + rkspi_enable_chip(regs, true); + + do { + u32 rx_level = readw(®s->rxflr); +#if defined(DEBUG) + statistics_rxlevels[rx_level]++; +#endif + chunk_size -= rx_level; + while (rx_level--) { + u16 val = readw(regs->rxdr); + *in++ = val & 0xff; + *in++ = val >> 8; + } + } while (chunk_size); + + rkspi_enable_chip(regs, false); + } + +#if defined(DEBUG) + debug("%s: observed rx_level during processing:\n", __func__); + for (int i = 0; i <= 32; ++i) + if (statistics_rxlevels[i]) + debug("\t%2d: %d\n", i, statistics_rxlevels[i]); +#endif + /* Restore the original transfer setup and return error-free. */ + writel(saved_ctrlr0, ®s->ctrlr0); + return 0; +} + static int rockchip_spi_xfer(struct udevice *dev, unsigned int bitlen, const void *dout, void *din, unsigned long flags) { @@ -317,7 +437,7 @@ static int rockchip_spi_xfer(struct udevice *dev, unsigned int bitlen, const u8 *out = dout; u8 *in = din; int toread, towrite; - int ret; + int ret = 0; debug("%s: dout=%p, din=%p, len=%x, flags=%lx\n", __func__, dout, din, len, flags); @@ -328,8 +448,18 @@ static int rockchip_spi_xfer(struct udevice *dev, unsigned int bitlen, if (flags & SPI_XFER_BEGIN) spi_cs_activate(dev, slave_plat->cs); + /* + * To ensure fast loading of firmware images (e.g. full U-Boot + * stage, ATF, Linux kernel) from SPI flash, we optimise the + * case of read-only transfers by using the full 16bits of each + * FIFO element. + */ + if (!out) + ret = rockchip_spi_16bit_reader(dev, &in, &len); + + /* This is the original 8bit reader/writer code */ while (len > 0) { - int todo = min(len, 0xffff); + int todo = min(len, ROCKCHIP_SPI_MAX_TRANLEN); rkspi_enable_chip(regs, false); writel(todo - 1, ®s->ctrlr1); @@ -352,9 +482,18 @@ static int rockchip_spi_xfer(struct udevice *dev, unsigned int bitlen, toread--; } } - ret = rkspi_wait_till_not_busy(regs); - if (ret) - break; + + /* + * In case that there's a transmit-component, we need to wait + * until the control goes idle before we can disable the SPI + * control logic (as this will implictly flush the FIFOs). + */ + if (out) { + ret = rkspi_wait_till_not_busy(regs); + if (ret) + break; + } + len -= todo; } @@ -371,10 +510,10 @@ static int rockchip_spi_set_speed(struct udevice *bus, uint speed) { struct rockchip_spi_priv *priv = dev_get_priv(bus); - if (speed > ROCKCHIP_SPI_MAX_RATE) - return -EINVAL; + /* Clamp to the maximum frequency specified in the DTS */ if (speed > priv->max_freq) speed = priv->max_freq; + priv->speed_hz = speed; return 0; @@ -401,8 +540,16 @@ static const struct dm_spi_ops rockchip_spi_ops = { */ }; +const struct rockchip_spi_params rk3399_spi_params = { + .master_manages_fifo = true, +}; + static const struct udevice_id rockchip_spi_ids[] = { { .compatible = "rockchip,rk3288-spi" }, + { .compatible = "rockchip,rk3368-spi", + .data = (ulong)&rk3399_spi_params }, + { .compatible = "rockchip,rk3399-spi", + .data = (ulong)&rk3399_spi_params }, { } };