diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.14/950-0028-clk-bcm2835-Read-max-core-clock-from-firmware.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.14/950-0028-clk-bcm2835-Read-max-core-clock-from-firmware.patch | 115 |
1 files changed, 0 insertions, 115 deletions
diff --git a/target/linux/brcm2708/patches-4.14/950-0028-clk-bcm2835-Read-max-core-clock-from-firmware.patch b/target/linux/brcm2708/patches-4.14/950-0028-clk-bcm2835-Read-max-core-clock-from-firmware.patch deleted file mode 100644 index b232c0c139..0000000000 --- a/target/linux/brcm2708/patches-4.14/950-0028-clk-bcm2835-Read-max-core-clock-from-firmware.patch +++ /dev/null @@ -1,115 +0,0 @@ -From a3927566a6d90268423ae58aad12a71b9bf39dd9 Mon Sep 17 00:00:00 2001 -From: Phil Elwell <phil@raspberrypi.org> -Date: Mon, 6 Mar 2017 09:06:18 +0000 -Subject: [PATCH 028/454] clk-bcm2835: Read max core clock from firmware - -The VPU is responsible for managing the core clock, usually under -direction from the bcm2835-cpufreq driver but not via the clk-bcm2835 -driver. Since the core frequency can change without warning, it is -safer to report the maximum clock rate to users of the core clock - -I2C, SPI and the mini UART - to err on the safe side when calculating -clock divisors. - -If the DT node for the clock driver includes a reference to the -firmware node, use the firmware API to query the maximum core clock -instead of reading the divider registers. - -Prior to this patch, a "100KHz" I2C bus was sometimes clocked at about -160KHz. In particular, switching to the 4.9 kernel was likely to break -SenseHAT usage on a Pi3. - -Signed-off-by: Phil Elwell <phil@raspberrypi.org> ---- - drivers/clk/bcm/clk-bcm2835.c | 39 ++++++++++++++++++++++++++++++++++- - 1 file changed, 38 insertions(+), 1 deletion(-) - ---- a/drivers/clk/bcm/clk-bcm2835.c -+++ b/drivers/clk/bcm/clk-bcm2835.c -@@ -45,6 +45,7 @@ - #include <linux/platform_device.h> - #include <linux/slab.h> - #include <dt-bindings/clock/bcm2835.h> -+#include <soc/bcm2835/raspberrypi-firmware.h> - - #define CM_PASSWORD 0x5a000000 - -@@ -299,6 +300,8 @@ - #define LOCK_TIMEOUT_NS 100000000 - #define BCM2835_MAX_FB_RATE 1750000000u - -+#define VCMSG_ID_CORE_CLOCK 4 -+ - /* - * Names of clocks used within the driver that need to be replaced - * with an external parent's name. This array is in the order that -@@ -317,6 +320,7 @@ static const char *const cprman_parent_n - struct bcm2835_cprman { - struct device *dev; - void __iomem *regs; -+ struct rpi_firmware *fw; - spinlock_t regs_lock; /* spinlock for all clocks */ - - /* -@@ -1032,6 +1036,30 @@ static unsigned long bcm2835_clock_get_r - return bcm2835_clock_rate_from_divisor(clock, parent_rate, div); - } - -+static unsigned long bcm2835_clock_get_rate_vpu(struct clk_hw *hw, -+ unsigned long parent_rate) -+{ -+ struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw); -+ struct bcm2835_cprman *cprman = clock->cprman; -+ -+ if (cprman->fw) { -+ struct { -+ u32 id; -+ u32 val; -+ } packet; -+ -+ packet.id = VCMSG_ID_CORE_CLOCK; -+ packet.val = 0; -+ -+ if (!rpi_firmware_property(cprman->fw, -+ RPI_FIRMWARE_GET_MAX_CLOCK_RATE, -+ &packet, sizeof(packet))) -+ return packet.val; -+ } -+ -+ return bcm2835_clock_get_rate(hw, parent_rate); -+} -+ - static void bcm2835_clock_wait_busy(struct bcm2835_clock *clock) - { - struct bcm2835_cprman *cprman = clock->cprman; -@@ -1321,7 +1349,7 @@ static int bcm2835_vpu_clock_is_on(struc - */ - static const struct clk_ops bcm2835_vpu_clock_clk_ops = { - .is_prepared = bcm2835_vpu_clock_is_on, -- .recalc_rate = bcm2835_clock_get_rate, -+ .recalc_rate = bcm2835_clock_get_rate_vpu, - .set_rate = bcm2835_clock_set_rate, - .determine_rate = bcm2835_clock_determine_rate, - .set_parent = bcm2835_clock_set_parent, -@@ -2201,6 +2229,7 @@ static int bcm2835_clk_probe(struct plat - struct resource *res; - const struct bcm2835_clk_desc *desc; - const size_t asize = ARRAY_SIZE(clk_desc_array); -+ struct device_node *fw_node; - size_t i; - u32 clk_id; - int ret; -@@ -2218,6 +2247,14 @@ static int bcm2835_clk_probe(struct plat - if (IS_ERR(cprman->regs)) - return PTR_ERR(cprman->regs); - -+ fw_node = of_parse_phandle(dev->of_node, "firmware", 0); -+ if (fw_node) { -+ struct rpi_firmware *fw = rpi_firmware_get(NULL); -+ if (!fw) -+ return -EPROBE_DEFER; -+ cprman->fw = fw; -+ } -+ - memset(bcm2835_clk_claimed, 0, sizeof(bcm2835_clk_claimed)); - for (i = 0; - !of_property_read_u32_index(pdev->dev.of_node, "claim-clocks", |