diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0225-Revert-bcm2835-sdhost-Precalc-divisors-and-overclock.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.4/0225-Revert-bcm2835-sdhost-Precalc-divisors-and-overclock.patch | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0225-Revert-bcm2835-sdhost-Precalc-divisors-and-overclock.patch b/target/linux/brcm2708/patches-4.4/0225-Revert-bcm2835-sdhost-Precalc-divisors-and-overclock.patch new file mode 100644 index 0000000000..e83ac3765b --- /dev/null +++ b/target/linux/brcm2708/patches-4.4/0225-Revert-bcm2835-sdhost-Precalc-divisors-and-overclock.patch @@ -0,0 +1,267 @@ +From 9524a87ecce1788c8f77d2b86deee65d11b4190d Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.org> +Date: Mon, 4 Apr 2016 12:35:32 +0100 +Subject: [PATCH 225/232] Revert "bcm2835-sdhost: Precalc divisors and + overclocks" + +This reverts commit 20260462773366a5734e5268dae0a4c179a21a2d. +--- + drivers/mmc/host/bcm2835-sdhost.c | 152 ++++++++++++++++---------------------- + 1 file changed, 64 insertions(+), 88 deletions(-) + +--- a/drivers/mmc/host/bcm2835-sdhost.c ++++ b/drivers/mmc/host/bcm2835-sdhost.c +@@ -154,15 +154,12 @@ struct bcm2835_host { + u32 pio_timeout; /* In jiffies */ + + int clock; /* Current clock speed */ +- int clocks[2]; + + bool slow_card; /* Force 11-bit divisor */ + + unsigned int max_clk; /* Max src clock freq */ +- unsigned int src_clks[2]; /* Min/max src clock freqs */ +- unsigned int cur_clk_idx; /* Index of current clock */ +- unsigned int next_clk_idx; /* Next clock index */ +- unsigned int cdivs[2]; ++ unsigned int min_clk; /* Min src clock freq */ ++ unsigned int cur_clk; /* Current src clock freq */ + + struct tasklet_struct finish_tasklet; /* Tasklet structures */ + +@@ -216,7 +213,7 @@ struct bcm2835_host { + u32 delay_after_stop; /* minimum time between stop and subsequent data transfer */ + u32 delay_after_this_stop; /* minimum time between this stop and subsequent data transfer */ + u32 overclock_50; /* frequency to use when 50MHz is requested (in MHz) */ +- u32 prev_overclock_50; ++ u32 overclock; /* Current frequency if overclocked, else zero */ + u32 pio_limit; /* Maximum block count for PIO (0 = always DMA) */ + + u32 sectors; /* Cached card size in sectors */ +@@ -1512,35 +1509,10 @@ static irqreturn_t bcm2835_sdhost_irq(in + return result; + } + +-static void bcm2835_sdhost_select_clock(struct bcm2835_host *host, int idx) +-{ +- unsigned int clock = host->clocks[idx]; +- unsigned int cdiv = host->cdivs[idx]; +- +- host->mmc->actual_clock = clock; +- host->ns_per_fifo_word = (1000000000/clock) * +- ((host->mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32); +- +- host->cdiv = cdiv; +- bcm2835_sdhost_write(host, host->cdiv, SDCDIV); +- +- /* Set the timeout to 500ms */ +- bcm2835_sdhost_write(host, clock/2, SDTOUT); +- +- host->cur_clk_idx = host->next_clk_idx = idx; +- +- if (host->debug) +- pr_info("%s: clock=%d -> src_clk=%d, cdiv=%x (actual %d)\n", +- mmc_hostname(host->mmc), host->clock, +- host->src_clks[idx], host->cdiv, +- host->mmc->actual_clock); +-} +- + void bcm2835_sdhost_set_clock(struct bcm2835_host *host) + { + int div = 0; /* Initialized for compiler warning */ + unsigned int clock = host->clock; +- int clk_idx; + + if (host->debug) + pr_info("%s: set_clock(%d)\n", mmc_hostname(host->mmc), clock); +@@ -1581,45 +1553,53 @@ void bcm2835_sdhost_set_clock(struct bcm + return; + } + +- /* Calculate the clock divisors */ +- for (clk_idx = 0; clk_idx <= host->variable_clock; clk_idx++) +- { +- unsigned int cur_clk = host->src_clks[clk_idx]; +- unsigned int actual_clock; ++ div = host->cur_clk / clock; ++ if (div < 2) ++ div = 2; ++ if ((host->cur_clk / div) > clock) ++ div++; ++ div -= 2; ++ ++ if (div > SDCDIV_MAX_CDIV) ++ div = SDCDIV_MAX_CDIV; ++ ++ clock = host->cur_clk / (div + 2); ++ host->mmc->actual_clock = clock; ++ ++ /* Calibrate some delays */ ++ ++ host->ns_per_fifo_word = (1000000000/clock) * ++ ((host->mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32); + +- div = cur_clk / clock; +- if (div < 2) +- div = 2; +- if ((cur_clk / div) > clock) +- div++; +- div -= 2; +- +- if (div > SDCDIV_MAX_CDIV) +- div = SDCDIV_MAX_CDIV; +- actual_clock = cur_clk / (div + 2); +- +- host->cdivs[clk_idx] = div; +- host->clocks[clk_idx] = actual_clock; +- +- if (host->overclock_50 != host->prev_overclock_50) { +- const char *clk_name = ""; +- if (host->variable_clock) +- clk_name = clk_idx ? " (turbo)" : " (normal)"; +- if (actual_clock > host->clock) +- pr_info("%s: overclocking to %dHz%s\n", +- mmc_hostname(host->mmc), +- actual_clock, clk_name); +- else if ((host->overclock_50 < 50) && (clk_idx == 0)) +- pr_info("%s: cancelling overclock%s\n", +- mmc_hostname(host->mmc), +- host->variable_clock ? "s" : ""); ++ if (clock > host->clock) { ++ /* Save the closest value, to make it easier ++ to reduce in the event of error */ ++ host->overclock_50 = (clock/MHZ); ++ ++ if (clock != host->overclock) { ++ pr_warn("%s: overclocking to %dHz\n", ++ mmc_hostname(host->mmc), clock); ++ host->overclock = clock; + } + } ++ else if (host->overclock) ++ { ++ host->overclock = 0; ++ if (clock == 50 * MHZ) ++ pr_warn("%s: cancelling overclock\n", ++ mmc_hostname(host->mmc)); ++ } + +- if (host->clock == 50*MHZ) +- host->prev_overclock_50 = host->overclock_50; ++ host->cdiv = div; ++ bcm2835_sdhost_write(host, host->cdiv, SDCDIV); + +- bcm2835_sdhost_select_clock(host, host->cur_clk_idx); ++ /* Set the timeout to 500ms */ ++ bcm2835_sdhost_write(host, host->mmc->actual_clock/2, SDTOUT); ++ ++ if (host->debug) ++ pr_info("%s: clock=%d -> cur_clk=%d, cdiv=%x (actual clock %d)\n", ++ mmc_hostname(host->mmc), host->clock, ++ host->cur_clk, host->cdiv, host->mmc->actual_clock); + } + + static void bcm2835_sdhost_request(struct mmc_host *mmc, struct mmc_request *mrq) +@@ -1677,9 +1657,6 @@ static void bcm2835_sdhost_request(struc + + spin_lock_irqsave(&host->lock, flags); + +- if (host->next_clk_idx != host->cur_clk_idx) +- bcm2835_sdhost_select_clock(host, host->next_clk_idx); +- + WARN_ON(host->mrq != NULL); + host->mrq = mrq; + +@@ -1742,7 +1719,11 @@ static int bcm2835_sdhost_cpufreq_callba + return NOTIFY_BAD; + break; + case CPUFREQ_POSTCHANGE: +- host->next_clk_idx = (freq->new > freq->old); ++ if (freq->new > freq->old) ++ host->cur_clk = host->max_clk; ++ else ++ host->cur_clk = host->min_clk; ++ bcm2835_sdhost_set_clock(host); + up(&host->cpufreq_semaphore); + break; + default: +@@ -1782,11 +1763,8 @@ static void bcm2835_sdhost_set_ios(struc + ios->clock, ios->power_mode, ios->bus_width, + ios->timing, ios->signal_voltage, ios->drv_type); + +- if (ios->clock && (host->cur_clk_idx == -1)) { +- unsigned int cur_clk = +- get_core_clock(RPI_FIRMWARE_GET_CLOCK_RATE); +- host->cur_clk_idx = (cur_clk == host->src_clks[0]) ? 0 : 1; +- } ++ if (ios->clock && !host->cur_clk) ++ host->cur_clk = get_core_clock(RPI_FIRMWARE_GET_CLOCK_RATE); + + spin_lock_irqsave(&host->lock, flags); + +@@ -1876,12 +1854,11 @@ static void bcm2835_sdhost_tasklet_finis + + /* Drop the overclock after any data corruption, or after any + error overclocked */ +- if (host->clock > 50*MHZ) { ++ if (host->overclock) { + if ((mrq->cmd && mrq->cmd->error) || + (mrq->data && mrq->data->error) || + (mrq->stop && mrq->stop->error)) { +- host->overclock_50 = (host->clock/MHZ) - 1; +- ++ host->overclock_50--; + pr_warn("%s: reducing overclock due to errors\n", + mmc_hostname(host->mmc)); + bcm2835_sdhost_set_clock(host); +@@ -2045,7 +2022,7 @@ static int bcm2835_sdhost_probe(struct p + struct bcm2835_host *host; + struct mmc_host *mmc; + const __be32 *addr; +- unsigned int max_clk, min_clk; ++ unsigned int max_clk; + int ret; + + pr_debug("bcm2835_sdhost_probe\n"); +@@ -2151,8 +2128,12 @@ static int bcm2835_sdhost_probe(struct p + else + mmc->caps |= MMC_CAP_4_BIT_DATA; + ++ ret = bcm2835_sdhost_add_host(host); ++ if (ret) ++ goto err; ++ + /* Query the core clock frequencies */ +- min_clk = get_core_clock(RPI_FIRMWARE_GET_MIN_CLOCK_RATE); ++ host->min_clk = get_core_clock(RPI_FIRMWARE_GET_MIN_CLOCK_RATE); + max_clk = get_core_clock(RPI_FIRMWARE_GET_MAX_CLOCK_RATE); + if (max_clk != host->max_clk) { + pr_warn("%s: Expected max clock %d, found %d\n", +@@ -2160,24 +2141,19 @@ static int bcm2835_sdhost_probe(struct p + host->max_clk = max_clk; + } + +- host->src_clks[0] = min_clk; +- host->cur_clk_idx = -1; +- if (max_clk != min_clk) { +- host->src_clks[1] = max_clk; ++ if (host->min_clk != host->max_clk) { + host->cpufreq_nb.notifier_call = + bcm2835_sdhost_cpufreq_callback; + sema_init(&host->cpufreq_semaphore, 1); + cpufreq_register_notifier(&host->cpufreq_nb, + CPUFREQ_TRANSITION_NOTIFIER); + host->variable_clock = 1; ++ host->cur_clk = 0; /* Get this later */ + } else { + host->variable_clock = 0; ++ host->cur_clk = host->max_clk; + } + +- ret = bcm2835_sdhost_add_host(host); +- if (ret) +- goto err; +- + platform_set_drvdata(pdev, host); + + pr_debug("bcm2835_sdhost_probe -> OK\n"); |