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authorIngo Molnar <mingo@kernel.org>2019-12-25 10:41:37 +0100
committerIngo Molnar <mingo@kernel.org>2019-12-25 10:41:37 +0100
commit1e5f8a308551b9816588e12bb795aeadebe37c4a (patch)
treebd71fc796fed24a3b7cc99df4a1d1bdaecc2b387 /drivers/memory/tegra/tegra20-emc.c
parentstop_machine: remove try_stop_cpus helper (diff)
parentLinux 5.5-rc3 (diff)
downloadlinux-1e5f8a308551b9816588e12bb795aeadebe37c4a.tar.xz
linux-1e5f8a308551b9816588e12bb795aeadebe37c4a.zip
Merge tag 'v5.5-rc3' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/memory/tegra/tegra20-emc.c')
-rw-r--r--drivers/memory/tegra/tegra20-emc.c134
1 files changed, 61 insertions, 73 deletions
diff --git a/drivers/memory/tegra/tegra20-emc.c b/drivers/memory/tegra/tegra20-emc.c
index 9ee5bef49e47..1b23b1c34476 100644
--- a/drivers/memory/tegra/tegra20-emc.c
+++ b/drivers/memory/tegra/tegra20-emc.c
@@ -6,10 +6,11 @@
*/
#include <linux/clk.h>
+#include <linux/clk/tegra.h>
#include <linux/completion.h>
#include <linux/err.h>
#include <linux/interrupt.h>
-#include <linux/iopoll.h>
+#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
@@ -21,6 +22,7 @@
#define EMC_INTSTATUS 0x000
#define EMC_INTMASK 0x004
+#define EMC_DBG 0x008
#define EMC_TIMING_CONTROL 0x028
#define EMC_RC 0x02c
#define EMC_RFC 0x030
@@ -79,6 +81,12 @@
#define EMC_REFRESH_OVERFLOW_INT BIT(3)
#define EMC_CLKCHANGE_COMPLETE_INT BIT(4)
+#define EMC_DBG_READ_MUX_ASSEMBLY BIT(0)
+#define EMC_DBG_WRITE_MUX_ACTIVE BIT(1)
+#define EMC_DBG_FORCE_UPDATE BIT(2)
+#define EMC_DBG_READ_DQM_CTRL BIT(9)
+#define EMC_DBG_CFG_PRIORITY BIT(24)
+
static const u16 emc_timing_registers[] = {
EMC_RC,
EMC_RFC,
@@ -137,9 +145,6 @@ struct tegra_emc {
struct device *dev;
struct completion clk_handshake_complete;
struct notifier_block clk_nb;
- struct clk *backup_clk;
- struct clk *emc_mux;
- struct clk *pll_m;
struct clk *clk;
void __iomem *regs;
@@ -219,7 +224,7 @@ static int emc_prepare_timing_change(struct tegra_emc *emc, unsigned long rate)
static int emc_complete_timing_change(struct tegra_emc *emc, bool flush)
{
- long timeout;
+ unsigned long timeout;
dev_dbg(emc->dev, "%s: flush %d\n", __func__, flush);
@@ -231,14 +236,10 @@ static int emc_complete_timing_change(struct tegra_emc *emc, bool flush)
}
timeout = wait_for_completion_timeout(&emc->clk_handshake_complete,
- usecs_to_jiffies(100));
+ msecs_to_jiffies(100));
if (timeout == 0) {
dev_err(emc->dev, "EMC-CAR handshake failed\n");
return -EIO;
- } else if (timeout < 0) {
- dev_err(emc->dev, "failed to wait for EMC-CAR handshake: %ld\n",
- timeout);
- return timeout;
}
return 0;
@@ -363,6 +364,13 @@ static int tegra_emc_load_timings_from_dt(struct tegra_emc *emc,
sort(emc->timings, emc->num_timings, sizeof(*timing), cmp_timings,
NULL);
+ dev_info(emc->dev,
+ "got %u timings for RAM code %u (min %luMHz max %luMHz)\n",
+ emc->num_timings,
+ tegra_read_ram_code(),
+ emc->timings[0].rate / 1000000,
+ emc->timings[emc->num_timings - 1].rate / 1000000);
+
return 0;
}
@@ -398,7 +406,7 @@ tegra_emc_find_node_by_ram_code(struct device *dev)
static int emc_setup_hw(struct tegra_emc *emc)
{
u32 intmask = EMC_REFRESH_OVERFLOW_INT | EMC_CLKCHANGE_COMPLETE_INT;
- u32 emc_cfg;
+ u32 emc_cfg, emc_dbg;
emc_cfg = readl_relaxed(emc->regs + EMC_CFG_2);
@@ -421,42 +429,53 @@ static int emc_setup_hw(struct tegra_emc *emc)
writel_relaxed(intmask, emc->regs + EMC_INTMASK);
writel_relaxed(intmask, emc->regs + EMC_INTSTATUS);
+ /* ensure that unwanted debug features are disabled */
+ emc_dbg = readl_relaxed(emc->regs + EMC_DBG);
+ emc_dbg |= EMC_DBG_CFG_PRIORITY;
+ emc_dbg &= ~EMC_DBG_READ_MUX_ASSEMBLY;
+ emc_dbg &= ~EMC_DBG_WRITE_MUX_ACTIVE;
+ emc_dbg &= ~EMC_DBG_FORCE_UPDATE;
+ writel_relaxed(emc_dbg, emc->regs + EMC_DBG);
+
return 0;
}
-static int emc_init(struct tegra_emc *emc, unsigned long rate)
+static long emc_round_rate(unsigned long rate,
+ unsigned long min_rate,
+ unsigned long max_rate,
+ void *arg)
{
- int err;
+ struct emc_timing *timing = NULL;
+ struct tegra_emc *emc = arg;
+ unsigned int i;
- err = clk_set_parent(emc->emc_mux, emc->backup_clk);
- if (err) {
- dev_err(emc->dev,
- "failed to reparent to backup source: %d\n", err);
- return err;
- }
+ min_rate = min(min_rate, emc->timings[emc->num_timings - 1].rate);
- err = clk_set_rate(emc->pll_m, rate);
- if (err) {
- dev_err(emc->dev,
- "failed to change pll_m rate: %d\n", err);
- return err;
- }
+ for (i = 0; i < emc->num_timings; i++) {
+ if (emc->timings[i].rate < rate && i != emc->num_timings - 1)
+ continue;
- err = clk_set_parent(emc->emc_mux, emc->pll_m);
- if (err) {
- dev_err(emc->dev,
- "failed to reparent to pll_m: %d\n", err);
- return err;
+ if (emc->timings[i].rate > max_rate) {
+ i = max(i, 1u) - 1;
+
+ if (emc->timings[i].rate < min_rate)
+ break;
+ }
+
+ if (emc->timings[i].rate < min_rate)
+ continue;
+
+ timing = &emc->timings[i];
+ break;
}
- err = clk_set_rate(emc->clk, rate);
- if (err) {
- dev_err(emc->dev,
- "failed to change emc rate: %d\n", err);
- return err;
+ if (!timing) {
+ dev_err(emc->dev, "no timing for rate %lu min %lu max %lu\n",
+ rate, min_rate, max_rate);
+ return -EINVAL;
}
- return 0;
+ return timing->rate;
}
static int tegra_emc_probe(struct platform_device *pdev)
@@ -515,57 +534,26 @@ static int tegra_emc_probe(struct platform_device *pdev)
return err;
}
+ tegra20_clk_set_emc_round_callback(emc_round_rate, emc);
+
emc->clk = devm_clk_get(&pdev->dev, "emc");
if (IS_ERR(emc->clk)) {
err = PTR_ERR(emc->clk);
dev_err(&pdev->dev, "failed to get emc clock: %d\n", err);
- return err;
- }
-
- emc->pll_m = clk_get_sys(NULL, "pll_m");
- if (IS_ERR(emc->pll_m)) {
- err = PTR_ERR(emc->pll_m);
- dev_err(&pdev->dev, "failed to get pll_m clock: %d\n", err);
- return err;
- }
-
- emc->backup_clk = clk_get_sys(NULL, "pll_p");
- if (IS_ERR(emc->backup_clk)) {
- err = PTR_ERR(emc->backup_clk);
- dev_err(&pdev->dev, "failed to get pll_p clock: %d\n", err);
- goto put_pll_m;
- }
-
- emc->emc_mux = clk_get_parent(emc->clk);
- if (IS_ERR(emc->emc_mux)) {
- err = PTR_ERR(emc->emc_mux);
- dev_err(&pdev->dev, "failed to get emc_mux clock: %d\n", err);
- goto put_backup;
+ goto unset_cb;
}
err = clk_notifier_register(emc->clk, &emc->clk_nb);
if (err) {
dev_err(&pdev->dev, "failed to register clk notifier: %d\n",
err);
- goto put_backup;
- }
-
- /* set DRAM clock rate to maximum */
- err = emc_init(emc, emc->timings[emc->num_timings - 1].rate);
- if (err) {
- dev_err(&pdev->dev, "failed to initialize EMC clock rate: %d\n",
- err);
- goto unreg_notifier;
+ goto unset_cb;
}
return 0;
-unreg_notifier:
- clk_notifier_unregister(emc->clk, &emc->clk_nb);
-put_backup:
- clk_put(emc->backup_clk);
-put_pll_m:
- clk_put(emc->pll_m);
+unset_cb:
+ tegra20_clk_set_emc_round_callback(NULL, NULL);
return err;
}