aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/brcm2708/patches-4.4/0225-bcm2835-sdhost-Firmware-manages-the-clock-divisor.patch
diff options
context:
space:
mode:
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0225-bcm2835-sdhost-Firmware-manages-the-clock-divisor.patch')
-rw-r--r--target/linux/brcm2708/patches-4.4/0225-bcm2835-sdhost-Firmware-manages-the-clock-divisor.patch226
1 files changed, 0 insertions, 226 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0225-bcm2835-sdhost-Firmware-manages-the-clock-divisor.patch b/target/linux/brcm2708/patches-4.4/0225-bcm2835-sdhost-Firmware-manages-the-clock-divisor.patch
deleted file mode 100644
index 0f2806455e..0000000000
--- a/target/linux/brcm2708/patches-4.4/0225-bcm2835-sdhost-Firmware-manages-the-clock-divisor.patch
+++ /dev/null
@@ -1,226 +0,0 @@
-From 2fd8e8397c3ae6e50fdb8b5224a195678cad9ed6 Mon Sep 17 00:00:00 2001
-From: Phil Elwell <phil@raspberrypi.org>
-Date: Mon, 4 Apr 2016 16:03:18 +0100
-Subject: [PATCH] bcm2835-sdhost: Firmware manages the clock divisor
-
-The bcm2835-sdhost driver hands control of the CDIV clock divisor
-register to matching firmware, allowing it to adjust to a changing
-core clock. This removes the need to use the performance governor or
-to enable io_is_busy on the on-demand governor in order to get the
-best SD performance.
-
-N.B. As SD clocks must be an integer divisor of the core clock, it is
-possible that the SD clock for "turbo" mode can be different (even
-lower) than "normal" mode.
-
-Signed-off-by: Phil Elwell <phil@raspberrypi.org>
----
- drivers/mmc/host/bcm2835-sdhost.c | 120 ++++++++++++++++++-----------
- include/soc/bcm2835/raspberrypi-firmware.h | 1 +
- 2 files changed, 74 insertions(+), 47 deletions(-)
-
---- a/drivers/mmc/host/bcm2835-sdhost.c
-+++ b/drivers/mmc/host/bcm2835-sdhost.c
-@@ -50,6 +50,7 @@
- #include <linux/of_dma.h>
- #include <linux/time.h>
- #include <linux/workqueue.h>
-+#include <soc/bcm2835/raspberrypi-firmware.h>
-
- #define DRIVER_NAME "sdhost-bcm2835"
-
-@@ -183,6 +184,7 @@ struct bcm2835_host {
- unsigned int use_sbc:1; /* Send CMD23 */
-
- unsigned int debug:1; /* Enable debug output */
-+ unsigned int firmware_sets_cdiv:1; /* Let the firmware manage the clock */
-
- /*DMA part*/
- struct dma_chan *dma_chan_rxtx; /* DMA channel for reads and writes */
-@@ -430,7 +432,7 @@ static void bcm2835_sdhost_reset_interna
- host->clock = 0;
- host->sectors = 0;
- bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
-- bcm2835_sdhost_write(host, host->cdiv, SDCDIV);
-+ bcm2835_sdhost_write(host, SDCDIV_MAX_CDIV, SDCDIV);
- mmiowb();
- }
-
-@@ -1534,62 +1536,75 @@ void bcm2835_sdhost_set_clock(struct bcm
-
- host->mmc->actual_clock = 0;
-
-- if (clock < 100000) {
-- /* Can't stop the clock, but make it as slow as possible
-- * to show willing
-- */
-- host->cdiv = SDCDIV_MAX_CDIV;
-- bcm2835_sdhost_write(host, host->cdiv, SDCDIV);
-- return;
-- }
--
-- div = host->max_clk / clock;
-- if (div < 2)
-- div = 2;
-- if ((host->max_clk / div) > clock)
-- div++;
-- div -= 2;
-+ if (host->firmware_sets_cdiv) {
-+ u32 msg[3] = { clock, 0, 0 };
-
-- if (div > SDCDIV_MAX_CDIV)
-- div = SDCDIV_MAX_CDIV;
-+ rpi_firmware_property(rpi_firmware_get(NULL),
-+ RPI_FIRMWARE_SET_SDHOST_CLOCK,
-+ &msg, sizeof(msg));
-
-- clock = host->max_clk / (div + 2);
-- host->mmc->actual_clock = clock;
-+ clock = max(msg[1], msg[2]);
-+ } else {
-+ if (clock < 100000) {
-+ /* Can't stop the clock, but make it as slow as
-+ * possible to show willing
-+ */
-+ host->cdiv = SDCDIV_MAX_CDIV;
-+ bcm2835_sdhost_write(host, host->cdiv, SDCDIV);
-+ return;
-+ }
-+
-+ div = host->max_clk / clock;
-+ if (div < 2)
-+ div = 2;
-+ if ((host->max_clk / div) > clock)
-+ div++;
-+ div -= 2;
-+
-+ if (div > SDCDIV_MAX_CDIV)
-+ div = SDCDIV_MAX_CDIV;
-+
-+ clock = host->max_clk / (div + 2);
-+
-+ host->cdiv = div;
-+ bcm2835_sdhost_write(host, host->cdiv, SDCDIV);
-+
-+ 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,
-+ clock);
-+ }
-
- /* Calibrate some delays */
-
- host->ns_per_fifo_word = (1000000000/clock) *
- ((host->mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32);
-
-- if (clock > input_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;
-+ if (input_clock == 50 * MHZ) {
-+ if (clock > input_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));
- }
- }
-- else if (host->overclock)
-- {
-- host->overclock = 0;
-- if (clock == 50 * MHZ)
-- pr_warn("%s: cancelling overclock\n",
-- mmc_hostname(host->mmc));
-- }
--
-- host->cdiv = div;
-- bcm2835_sdhost_write(host, host->cdiv, SDCDIV);
-
- /* Set the timeout to 500ms */
-- bcm2835_sdhost_write(host, host->mmc->actual_clock/2, SDTOUT);
-+ bcm2835_sdhost_write(host, 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);
-+ host->mmc->actual_clock = clock;
- }
-
- static void bcm2835_sdhost_request(struct mmc_host *mmc, struct mmc_request *mrq)
-@@ -1704,11 +1719,6 @@ static void bcm2835_sdhost_set_ios(struc
-
- log_event("IOS<", ios->clock, 0);
-
-- if (!ios->clock || ios->clock != host->clock) {
-- bcm2835_sdhost_set_clock(host, ios->clock);
-- host->clock = ios->clock;
-- }
--
- /* set bus width */
- host->hcfg &= ~SDHCFG_WIDE_EXT_BUS;
- if (ios->bus_width == MMC_BUS_WIDTH_4)
-@@ -1721,6 +1731,11 @@ static void bcm2835_sdhost_set_ios(struc
-
- bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
-
-+ if (!ios->clock || ios->clock != host->clock) {
-+ bcm2835_sdhost_set_clock(host, ios->clock);
-+ host->clock = ios->clock;
-+ }
-+
- mmiowb();
-
- spin_unlock_irqrestore(&host->lock, flags);
-@@ -1953,6 +1968,7 @@ static int bcm2835_sdhost_probe(struct p
- struct bcm2835_host *host;
- struct mmc_host *mmc;
- const __be32 *addr;
-+ u32 msg[3];
- int ret;
-
- pr_debug("bcm2835_sdhost_probe\n");
-@@ -2058,6 +2074,16 @@ static int bcm2835_sdhost_probe(struct p
- else
- mmc->caps |= MMC_CAP_4_BIT_DATA;
-
-+ msg[0] = 0;
-+ msg[1] = ~0;
-+ msg[2] = ~0;
-+
-+ rpi_firmware_property(rpi_firmware_get(NULL),
-+ RPI_FIRMWARE_SET_SDHOST_CLOCK,
-+ &msg, sizeof(msg));
-+
-+ host->firmware_sets_cdiv = (msg[1] != ~0);
-+
- ret = bcm2835_sdhost_add_host(host);
- if (ret)
- goto err;
---- a/include/soc/bcm2835/raspberrypi-firmware.h
-+++ b/include/soc/bcm2835/raspberrypi-firmware.h
-@@ -79,6 +79,7 @@ enum rpi_firmware_property_tag {
- RPI_FIRMWARE_SET_VOLTAGE = 0x00038003,
- RPI_FIRMWARE_SET_TURBO = 0x00038009,
- RPI_FIRMWARE_SET_CUSTOMER_OTP = 0x00038021,
-+ RPI_FIRMWARE_SET_SDHOST_CLOCK = 0x00038042,
-
- /* Dispmanx TAGS */
- RPI_FIRMWARE_FRAMEBUFFER_ALLOCATE = 0x00040001,
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-28 06:11:06 +0000