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Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0216-bcm2835-sdhost-Adjust-to-core-clock-changes.patch')
-rw-r--r--target/linux/brcm2708/patches-4.4/0216-bcm2835-sdhost-Adjust-to-core-clock-changes.patch339
1 files changed, 0 insertions, 339 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0216-bcm2835-sdhost-Adjust-to-core-clock-changes.patch b/target/linux/brcm2708/patches-4.4/0216-bcm2835-sdhost-Adjust-to-core-clock-changes.patch
deleted file mode 100644
index cfc32c0670..0000000000
--- a/target/linux/brcm2708/patches-4.4/0216-bcm2835-sdhost-Adjust-to-core-clock-changes.patch
+++ /dev/null
@@ -1,339 +0,0 @@
-From afa73f51ed48ae715560e200edcdb7cc85a1e43b Mon Sep 17 00:00:00 2001
-From: Phil Elwell <phil@raspberrypi.org>
-Date: Wed, 30 Mar 2016 16:33:09 +0100
-Subject: [PATCH] bcm2835-sdhost: Adjust to core clock changes
-
-The SDHOST block uses the core clock, so previously it has been
-necessary to prevent the core clock from changing in order to maintain
-performance and prevent accidental SD bus overclocking.
-
-With this patch the sdhost driver is notified of clock changes, allowing
-it to delay them while an SD access is outstanding and to delay new SD
-accesses while the clock is changing. This feature is disabled in the
-case where the core frequency can never change.
-
-Now that the driver copes with changes to the core clock, it is safe
-to disable the io_is_busy feature of the on-demand governor.
-
-Signed-off-by: Phil Elwell <phil@raspberrypi.org>
----
- drivers/mmc/host/Kconfig | 1 +
- drivers/mmc/host/bcm2835-sdhost.c | 140 ++++++++++++++++++++++++++++++++------
- 2 files changed, 119 insertions(+), 22 deletions(-)
-
---- a/drivers/mmc/host/Kconfig
-+++ b/drivers/mmc/host/Kconfig
-@@ -36,6 +36,7 @@ config MMC_BCM2835_PIO_DMA_BARRIER
- config MMC_BCM2835_SDHOST
- tristate "Support for the SDHost controller on BCM2708/9"
- depends on MACH_BCM2708 || MACH_BCM2709 || ARCH_BCM2835
-+ depends on RASPBERRYPI_FIRMWARE
- help
- This selects the SDHost controller on BCM2835/6.
-
---- a/drivers/mmc/host/bcm2835-sdhost.c
-+++ b/drivers/mmc/host/bcm2835-sdhost.c
-@@ -50,6 +50,10 @@
- #include <linux/of_dma.h>
- #include <linux/time.h>
- #include <linux/workqueue.h>
-+#include <linux/cpufreq.h>
-+#include <linux/semaphore.h>
-+#include <soc/bcm2835/raspberrypi-firmware.h>
-+
-
- #define DRIVER_NAME "sdhost-bcm2835"
-
-@@ -136,6 +140,8 @@
-
- #define MHZ 1000000
-
-+#define RPI_FIRMWARE_CLOCK_CORE 4
-+
-
- struct bcm2835_host {
- spinlock_t lock;
-@@ -151,7 +157,9 @@ struct bcm2835_host {
-
- bool slow_card; /* Force 11-bit divisor */
-
-- unsigned int max_clk; /* Max possible freq */
-+ unsigned int max_clk; /* Max src clock freq */
-+ unsigned int min_clk; /* Min src clock freq */
-+ unsigned int cur_clk; /* Current src clock freq */
-
- struct tasklet_struct finish_tasklet; /* Tasklet structures */
-
-@@ -183,6 +191,7 @@ struct bcm2835_host {
- unsigned int use_sbc:1; /* Send CMD23 */
-
- unsigned int debug:1; /* Enable debug output */
-+ unsigned int variable_clock:1; /* The core clock may change */
-
- /*DMA part*/
- struct dma_chan *dma_chan_rxtx; /* DMA channel for reads and writes */
-@@ -208,6 +217,9 @@ struct bcm2835_host {
- u32 pio_limit; /* Maximum block count for PIO (0 = always DMA) */
-
- u32 sectors; /* Cached card size in sectors */
-+
-+ struct notifier_block cpufreq_nb; /* The cpufreq callback list item */
-+ struct semaphore cpufreq_semaphore; /* Interlock between SD activity and cpufreq changes */
- };
-
- #if ENABLE_LOG
-@@ -227,6 +239,10 @@ static u32 sdhost_log_idx;
- static spinlock_t log_lock;
- static void __iomem *timer_base;
-
-+static int bcm2835_sdhost_cpufreq_callback(struct notifier_block *nb,
-+ unsigned long action, void *data);
-+static unsigned int get_core_clock(unsigned int mode);
-+
- #define LOG_ENTRIES (256*1)
- #define LOG_SIZE (sizeof(LOG_ENTRY_T)*LOG_ENTRIES)
-
-@@ -448,20 +464,14 @@ static void bcm2835_sdhost_reset(struct
-
- static void bcm2835_sdhost_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
-
--static void bcm2835_sdhost_init(struct bcm2835_host *host, int soft)
-+static void bcm2835_sdhost_init(struct bcm2835_host *host)
- {
-- pr_debug("bcm2835_sdhost_init(%d)\n", soft);
-+ pr_debug("bcm2835_sdhost_init()\n");
-
- /* Set interrupt enables */
- host->hcfg = SDHCFG_BUSY_IRPT_EN;
-
- bcm2835_sdhost_reset_internal(host);
--
-- if (soft) {
-- /* force clock reconfiguration */
-- host->clock = 0;
-- bcm2835_sdhost_set_ios(host->mmc, &host->mmc->ios);
-- }
- }
-
- static void bcm2835_sdhost_wait_transfer_complete(struct bcm2835_host *host)
-@@ -1499,10 +1509,10 @@ static irqreturn_t bcm2835_sdhost_irq(in
- return result;
- }
-
--void bcm2835_sdhost_set_clock(struct bcm2835_host *host, unsigned int clock)
-+void bcm2835_sdhost_set_clock(struct bcm2835_host *host)
- {
- int div = 0; /* Initialized for compiler warning */
-- unsigned int input_clock = clock;
-+ unsigned int clock = host->clock;
-
- if (host->debug)
- pr_info("%s: set_clock(%d)\n", mmc_hostname(host->mmc), clock);
-@@ -1543,17 +1553,17 @@ void bcm2835_sdhost_set_clock(struct bcm
- return;
- }
-
-- div = host->max_clk / clock;
-+ div = host->cur_clk / clock;
- if (div < 2)
- div = 2;
-- if ((host->max_clk / div) > clock)
-+ if ((host->cur_clk / div) > clock)
- div++;
- div -= 2;
-
- if (div > SDCDIV_MAX_CDIV)
- div = SDCDIV_MAX_CDIV;
-
-- clock = host->max_clk / (div + 2);
-+ clock = host->cur_clk / (div + 2);
- host->mmc->actual_clock = clock;
-
- /* Calibrate some delays */
-@@ -1561,7 +1571,7 @@ void bcm2835_sdhost_set_clock(struct bcm
- host->ns_per_fifo_word = (1000000000/clock) *
- ((host->mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32);
-
-- if (clock > input_clock) {
-+ if (clock > host->clock) {
- /* Save the closest value, to make it easier
- to reduce in the event of error */
- host->overclock_50 = (clock/MHZ);
-@@ -1587,9 +1597,9 @@ void bcm2835_sdhost_set_clock(struct bcm
- bcm2835_sdhost_write(host, host->mmc->actual_clock/2, SDTOUT);
-
- if (host->debug)
-- pr_info("%s: clock=%d -> max_clk=%d, cdiv=%x (actual clock %d)\n",
-- mmc_hostname(host->mmc), input_clock,
-- host->max_clk, host->cdiv, host->mmc->actual_clock);
-+ 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)
-@@ -1638,6 +1648,13 @@ static void bcm2835_sdhost_request(struc
- (mrq->data->blocks > host->pio_limit))
- bcm2835_sdhost_prepare_dma(host, mrq->data);
-
-+ if (host->variable_clock &&
-+ (down_killable(&host->cpufreq_semaphore) != 0)) {
-+ mrq->cmd->error = -EINTR;
-+ mmc_request_done(mmc, mrq);
-+ return;
-+ }
-+
- spin_lock_irqsave(&host->lock, flags);
-
- WARN_ON(host->mrq != NULL);
-@@ -1687,6 +1704,52 @@ static void bcm2835_sdhost_request(struc
- spin_unlock_irqrestore(&host->lock, flags);
- }
-
-+static int bcm2835_sdhost_cpufreq_callback(struct notifier_block *nb,
-+ unsigned long action, void *data)
-+{
-+ struct cpufreq_freqs *freq = data;
-+ struct bcm2835_host *host;
-+
-+ host = container_of(nb, struct bcm2835_host, cpufreq_nb);
-+
-+ if (freq->cpu == 0) {
-+ switch (action) {
-+ case CPUFREQ_PRECHANGE:
-+ if (down_killable(&host->cpufreq_semaphore) != 0)
-+ return NOTIFY_BAD;
-+ break;
-+ case CPUFREQ_POSTCHANGE:
-+ 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:
-+ break;
-+ }
-+ }
-+ return NOTIFY_OK;
-+}
-+
-+static unsigned int get_core_clock(unsigned int mode)
-+{
-+ struct rpi_firmware *fw = rpi_firmware_get(NULL);
-+ struct {
-+ u32 id;
-+ u32 val;
-+ } packet;
-+ int ret;
-+
-+ packet.id = RPI_FIRMWARE_CLOCK_CORE;
-+ ret = rpi_firmware_property(fw, mode, &packet, sizeof(packet));
-+ if (ret)
-+ return 0;
-+
-+ return packet.val;
-+}
-+
- static void bcm2835_sdhost_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
- {
-
-@@ -1700,13 +1763,16 @@ 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)
-+ host->cur_clk = get_core_clock(RPI_FIRMWARE_GET_CLOCK_RATE);
-+
- spin_lock_irqsave(&host->lock, flags);
-
- log_event("IOS<", ios->clock, 0);
-
- if (!ios->clock || ios->clock != host->clock) {
-- bcm2835_sdhost_set_clock(host, ios->clock);
- host->clock = ios->clock;
-+ bcm2835_sdhost_set_clock(host);
- }
-
- /* set bus width */
-@@ -1795,7 +1861,7 @@ static void bcm2835_sdhost_tasklet_finis
- host->overclock_50--;
- pr_warn("%s: reducing overclock due to errors\n",
- mmc_hostname(host->mmc));
-- bcm2835_sdhost_set_clock(host,50*MHZ);
-+ bcm2835_sdhost_set_clock(host);
- mrq->cmd->error = -EILSEQ;
- mrq->cmd->retries = 1;
- }
-@@ -1813,6 +1879,9 @@ static void bcm2835_sdhost_tasklet_finis
-
- spin_unlock_irqrestore(&host->lock, flags);
-
-+ if (host->variable_clock)
-+ up(&host->cpufreq_semaphore);
-+
- if (terminate_chan)
- {
- int err = dmaengine_terminate_all(terminate_chan);
-@@ -1915,10 +1984,10 @@ int bcm2835_sdhost_add_host(struct bcm28
- setup_timer(&host->timer, bcm2835_sdhost_timeout,
- (unsigned long)host);
-
-- bcm2835_sdhost_init(host, 0);
-+ bcm2835_sdhost_init(host);
-
- ret = request_irq(host->irq, bcm2835_sdhost_irq, 0 /*IRQF_SHARED*/,
-- mmc_hostname(mmc), host);
-+ mmc_hostname(mmc), host);
- if (ret) {
- pr_err("%s: failed to request IRQ %d: %d\n",
- mmc_hostname(mmc), host->irq, ret);
-@@ -1953,6 +2022,7 @@ static int bcm2835_sdhost_probe(struct p
- struct bcm2835_host *host;
- struct mmc_host *mmc;
- const __be32 *addr;
-+ unsigned int max_clk;
- int ret;
-
- pr_debug("bcm2835_sdhost_probe\n");
-@@ -2062,6 +2132,28 @@ static int bcm2835_sdhost_probe(struct p
- if (ret)
- goto err;
-
-+ /* Query the core clock frequencies */
-+ 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",
-+ mmc_hostname(mmc), host->max_clk, max_clk);
-+ host->max_clk = 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;
-+ }
-+
- platform_set_drvdata(pdev, host);
-
- pr_debug("bcm2835_sdhost_probe -> OK\n");
-@@ -2081,6 +2173,10 @@ static int bcm2835_sdhost_remove(struct
-
- pr_debug("bcm2835_sdhost_remove\n");
-
-+ if (host->variable_clock)
-+ cpufreq_unregister_notifier(&host->cpufreq_nb,
-+ CPUFREQ_TRANSITION_NOTIFIER);
-+
- mmc_remove_host(host->mmc);
-
- bcm2835_sdhost_set_power(host, false);
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-11 23:16:49 +0000