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authorVarun Sethi <Varun.Sethi@freescale.com>2013-07-15 10:20:57 +0530
committerJoerg Roedel <joro@8bytes.org>2013-08-14 11:38:34 +0200
commit695093e38c3ef63fcb43a2840ed865efa20671d5 (patch)
treeb4e474176ced242d9bd5d1dadfb08c7cc817e9bd /drivers/iommu/fsl_pamu.c
parent7cabf491eb6d52ea7f166b287702890cae0c803d (diff)
downloadlwn-695093e38c3ef63fcb43a2840ed865efa20671d5.tar.gz
lwn-695093e38c3ef63fcb43a2840ed865efa20671d5.zip
iommu/fsl: Freescale PAMU driver and iommu implementation.
Following is a brief description of the PAMU hardware: PAMU determines what action to take and whether to authorize the action on the basis of the memory address, a Logical IO Device Number (LIODN), and PAACT table (logically) indexed by LIODN and address. Hardware devices which need to access memory must provide an LIODN in addition to the memory address. Peripheral Access Authorization and Control Tables (PAACTs) are the primary data structures used by PAMU. A PAACT is a table of peripheral access authorization and control entries (PAACE).Each PAACE defines the range of I/O bus address space that is accessible by the LIOD and the associated access capabilities. There are two types of PAACTs: primary PAACT (PPAACT) and secondary PAACT (SPAACT).A given physical I/O device may be able to act as one or more independent logical I/O devices (LIODs). Each such logical I/O device is assigned an identifier called logical I/O device number (LIODN). A LIODN is allocated a contiguous portion of the I/O bus address space called the DSA window for performing DSA operations. The DSA window may optionally be divided into multiple sub-windows, each of which may be used to map to a region in system storage space. The first sub-window is referred to as the primary sub-window and the remaining are called secondary sub-windows. This patch provides the PAMU driver (fsl_pamu.c) and the corresponding IOMMU API implementation (fsl_pamu_domain.c). The PAMU hardware driver (fsl_pamu.c) has been derived from the work done by Ashish Kalra and Timur Tabi. [For iommu group support] Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Timur Tabi <timur@tabi.org> Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
Diffstat (limited to 'drivers/iommu/fsl_pamu.c')
-rw-r--r--drivers/iommu/fsl_pamu.c1309
1 files changed, 1309 insertions, 0 deletions
diff --git a/drivers/iommu/fsl_pamu.c b/drivers/iommu/fsl_pamu.c
new file mode 100644
index 000000000000..a831fee32399
--- /dev/null
+++ b/drivers/iommu/fsl_pamu.c
@@ -0,0 +1,1309 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ */
+
+#define pr_fmt(fmt) "fsl-pamu: %s: " fmt, __func__
+
+#include <linux/init.h>
+#include <linux/iommu.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/of_platform.h>
+#include <linux/bootmem.h>
+#include <linux/genalloc.h>
+#include <asm/io.h>
+#include <asm/bitops.h>
+#include <asm/fsl_guts.h>
+
+#include "fsl_pamu.h"
+
+/* define indexes for each operation mapping scenario */
+#define OMI_QMAN 0x00
+#define OMI_FMAN 0x01
+#define OMI_QMAN_PRIV 0x02
+#define OMI_CAAM 0x03
+
+#define make64(high, low) (((u64)(high) << 32) | (low))
+
+struct pamu_isr_data {
+ void __iomem *pamu_reg_base; /* Base address of PAMU regs*/
+ unsigned int count; /* The number of PAMUs */
+};
+
+static struct paace *ppaact;
+static struct paace *spaact;
+static struct ome *omt;
+
+/*
+ * Table for matching compatible strings, for device tree
+ * guts node, for QorIQ SOCs.
+ * "fsl,qoriq-device-config-2.0" corresponds to T4 & B4
+ * SOCs. For the older SOCs "fsl,qoriq-device-config-1.0"
+ * string would be used.
+*/
+static const struct of_device_id guts_device_ids[] = {
+ { .compatible = "fsl,qoriq-device-config-1.0", },
+ { .compatible = "fsl,qoriq-device-config-2.0", },
+ {}
+};
+
+
+/*
+ * Table for matching compatible strings, for device tree
+ * L3 cache controller node.
+ * "fsl,t4240-l3-cache-controller" corresponds to T4,
+ * "fsl,b4860-l3-cache-controller" corresponds to B4 &
+ * "fsl,p4080-l3-cache-controller" corresponds to other,
+ * SOCs.
+*/
+static const struct of_device_id l3_device_ids[] = {
+ { .compatible = "fsl,t4240-l3-cache-controller", },
+ { .compatible = "fsl,b4860-l3-cache-controller", },
+ { .compatible = "fsl,p4080-l3-cache-controller", },
+ {}
+};
+
+/* maximum subwindows permitted per liodn */
+static u32 max_subwindow_count;
+
+/* Pool for fspi allocation */
+struct gen_pool *spaace_pool;
+
+/**
+ * pamu_get_max_subwin_cnt() - Return the maximum supported
+ * subwindow count per liodn.
+ *
+ */
+u32 pamu_get_max_subwin_cnt()
+{
+ return max_subwindow_count;
+}
+
+/**
+ * pamu_get_ppaace() - Return the primary PACCE
+ * @liodn: liodn PAACT index for desired PAACE
+ *
+ * Returns the ppace pointer upon success else return
+ * null.
+ */
+static struct paace *pamu_get_ppaace(int liodn)
+{
+ if (!ppaact || liodn >= PAACE_NUMBER_ENTRIES) {
+ pr_debug("PPAACT doesn't exist\n");
+ return NULL;
+ }
+
+ return &ppaact[liodn];
+}
+
+/**
+ * pamu_enable_liodn() - Set valid bit of PACCE
+ * @liodn: liodn PAACT index for desired PAACE
+ *
+ * Returns 0 upon success else error code < 0 returned
+ */
+int pamu_enable_liodn(int liodn)
+{
+ struct paace *ppaace;
+
+ ppaace = pamu_get_ppaace(liodn);
+ if (!ppaace) {
+ pr_debug("Invalid primary paace entry\n");
+ return -ENOENT;
+ }
+
+ if (!get_bf(ppaace->addr_bitfields, PPAACE_AF_WSE)) {
+ pr_debug("liodn %d not configured\n", liodn);
+ return -EINVAL;
+ }
+
+ /* Ensure that all other stores to the ppaace complete first */
+ mb();
+
+ set_bf(ppaace->addr_bitfields, PAACE_AF_V, PAACE_V_VALID);
+ mb();
+
+ return 0;
+}
+
+/**
+ * pamu_disable_liodn() - Clears valid bit of PACCE
+ * @liodn: liodn PAACT index for desired PAACE
+ *
+ * Returns 0 upon success else error code < 0 returned
+ */
+int pamu_disable_liodn(int liodn)
+{
+ struct paace *ppaace;
+
+ ppaace = pamu_get_ppaace(liodn);
+ if (!ppaace) {
+ pr_debug("Invalid primary paace entry\n");
+ return -ENOENT;
+ }
+
+ set_bf(ppaace->addr_bitfields, PAACE_AF_V, PAACE_V_INVALID);
+ mb();
+
+ return 0;
+}
+
+/* Derive the window size encoding for a particular PAACE entry */
+static unsigned int map_addrspace_size_to_wse(phys_addr_t addrspace_size)
+{
+ /* Bug if not a power of 2 */
+ BUG_ON(!is_power_of_2(addrspace_size));
+
+ /* window size is 2^(WSE+1) bytes */
+ return __ffs(addrspace_size) - 1;
+}
+
+/* Derive the PAACE window count encoding for the subwindow count */
+static unsigned int map_subwindow_cnt_to_wce(u32 subwindow_cnt)
+{
+ /* window count is 2^(WCE+1) bytes */
+ return __ffs(subwindow_cnt) - 1;
+}
+
+/*
+ * Set the PAACE type as primary and set the coherency required domain
+ * attribute
+ */
+static void pamu_init_ppaace(struct paace *ppaace)
+{
+ set_bf(ppaace->addr_bitfields, PAACE_AF_PT, PAACE_PT_PRIMARY);
+
+ set_bf(ppaace->domain_attr.to_host.coherency_required, PAACE_DA_HOST_CR,
+ PAACE_M_COHERENCE_REQ);
+}
+
+/*
+ * Set the PAACE type as secondary and set the coherency required domain
+ * attribute.
+ */
+static void pamu_init_spaace(struct paace *spaace)
+{
+ set_bf(spaace->addr_bitfields, PAACE_AF_PT, PAACE_PT_SECONDARY);
+ set_bf(spaace->domain_attr.to_host.coherency_required, PAACE_DA_HOST_CR,
+ PAACE_M_COHERENCE_REQ);
+}
+
+/*
+ * Return the spaace (corresponding to the secondary window index)
+ * for a particular ppaace.
+ */
+static struct paace *pamu_get_spaace(struct paace *paace, u32 wnum)
+{
+ u32 subwin_cnt;
+ struct paace *spaace = NULL;
+
+ subwin_cnt = 1UL << (get_bf(paace->impl_attr, PAACE_IA_WCE) + 1);
+
+ if (wnum < subwin_cnt)
+ spaace = &spaact[paace->fspi + wnum];
+ else
+ pr_debug("secondary paace out of bounds\n");
+
+ return spaace;
+}
+
+/**
+ * pamu_get_fspi_and_allocate() - Allocates fspi index and reserves subwindows
+ * required for primary PAACE in the secondary
+ * PAACE table.
+ * @subwin_cnt: Number of subwindows to be reserved.
+ *
+ * A PPAACE entry may have a number of associated subwindows. A subwindow
+ * corresponds to a SPAACE entry in the SPAACT table. Each PAACE entry stores
+ * the index (fspi) of the first SPAACE entry in the SPAACT table. This
+ * function returns the index of the first SPAACE entry. The remaining
+ * SPAACE entries are reserved contiguously from that index.
+ *
+ * Returns a valid fspi index in the range of 0 - SPAACE_NUMBER_ENTRIES on success.
+ * If no SPAACE entry is available or the allocator can not reserve the required
+ * number of contiguous entries function returns ULONG_MAX indicating a failure.
+ *
+*/
+static unsigned long pamu_get_fspi_and_allocate(u32 subwin_cnt)
+{
+ unsigned long spaace_addr;
+
+ spaace_addr = gen_pool_alloc(spaace_pool, subwin_cnt * sizeof(struct paace));
+ if (!spaace_addr)
+ return ULONG_MAX;
+
+ return (spaace_addr - (unsigned long)spaact) / (sizeof(struct paace));
+}
+
+/* Release the subwindows reserved for a particular LIODN */
+void pamu_free_subwins(int liodn)
+{
+ struct paace *ppaace;
+ u32 subwin_cnt, size;
+
+ ppaace = pamu_get_ppaace(liodn);
+ if (!ppaace) {
+ pr_debug("Invalid liodn entry\n");
+ return;
+ }
+
+ if (get_bf(ppaace->addr_bitfields, PPAACE_AF_MW)) {
+ subwin_cnt = 1UL << (get_bf(ppaace->impl_attr, PAACE_IA_WCE) + 1);
+ size = (subwin_cnt - 1) * sizeof(struct paace);
+ gen_pool_free(spaace_pool, (unsigned long)&spaact[ppaace->fspi], size);
+ set_bf(ppaace->addr_bitfields, PPAACE_AF_MW, 0);
+ }
+}
+
+/*
+ * Function used for updating stash destination for the coressponding
+ * LIODN.
+ */
+int pamu_update_paace_stash(int liodn, u32 subwin, u32 value)
+{
+ struct paace *paace;
+
+ paace = pamu_get_ppaace(liodn);
+ if (!paace) {
+ pr_debug("Invalid liodn entry\n");
+ return -ENOENT;
+ }
+ if (subwin) {
+ paace = pamu_get_spaace(paace, subwin - 1);
+ if (!paace) {
+ return -ENOENT;
+ }
+ }
+ set_bf(paace->impl_attr, PAACE_IA_CID, value);
+
+ mb();
+
+ return 0;
+}
+
+/* Disable a subwindow corresponding to the LIODN */
+int pamu_disable_spaace(int liodn, u32 subwin)
+{
+ struct paace *paace;
+
+ paace = pamu_get_ppaace(liodn);
+ if (!paace) {
+ pr_debug("Invalid liodn entry\n");
+ return -ENOENT;
+ }
+ if (subwin) {
+ paace = pamu_get_spaace(paace, subwin - 1);
+ if (!paace) {
+ return -ENOENT;
+ }
+ set_bf(paace->addr_bitfields, PAACE_AF_V,
+ PAACE_V_INVALID);
+ } else {
+ set_bf(paace->addr_bitfields, PAACE_AF_AP,
+ PAACE_AP_PERMS_DENIED);
+ }
+
+ mb();
+
+ return 0;
+}
+
+
+/**
+ * pamu_config_paace() - Sets up PPAACE entry for specified liodn
+ *
+ * @liodn: Logical IO device number
+ * @win_addr: starting address of DSA window
+ * @win-size: size of DSA window
+ * @omi: Operation mapping index -- if ~omi == 0 then omi not defined
+ * @rpn: real (true physical) page number
+ * @stashid: cache stash id for associated cpu -- if ~stashid == 0 then
+ * stashid not defined
+ * @snoopid: snoop id for hardware coherency -- if ~snoopid == 0 then
+ * snoopid not defined
+ * @subwin_cnt: number of sub-windows
+ * @prot: window permissions
+ *
+ * Returns 0 upon success else error code < 0 returned
+ */
+int pamu_config_ppaace(int liodn, phys_addr_t win_addr, phys_addr_t win_size,
+ u32 omi, unsigned long rpn, u32 snoopid, u32 stashid,
+ u32 subwin_cnt, int prot)
+{
+ struct paace *ppaace;
+ unsigned long fspi;
+
+ if (!is_power_of_2(win_size) || win_size < PAMU_PAGE_SIZE) {
+ pr_debug("window size too small or not a power of two %llx\n", win_size);
+ return -EINVAL;
+ }
+
+ if (win_addr & (win_size - 1)) {
+ pr_debug("window address is not aligned with window size\n");
+ return -EINVAL;
+ }
+
+ ppaace = pamu_get_ppaace(liodn);
+ if (!ppaace) {
+ return -ENOENT;
+ }
+
+ /* window size is 2^(WSE+1) bytes */
+ set_bf(ppaace->addr_bitfields, PPAACE_AF_WSE,
+ map_addrspace_size_to_wse(win_size));
+
+ pamu_init_ppaace(ppaace);
+
+ ppaace->wbah = win_addr >> (PAMU_PAGE_SHIFT + 20);
+ set_bf(ppaace->addr_bitfields, PPAACE_AF_WBAL,
+ (win_addr >> PAMU_PAGE_SHIFT));
+
+ /* set up operation mapping if it's configured */
+ if (omi < OME_NUMBER_ENTRIES) {
+ set_bf(ppaace->impl_attr, PAACE_IA_OTM, PAACE_OTM_INDEXED);
+ ppaace->op_encode.index_ot.omi = omi;
+ } else if (~omi != 0) {
+ pr_debug("bad operation mapping index: %d\n", omi);
+ return -EINVAL;
+ }
+
+ /* configure stash id */
+ if (~stashid != 0)
+ set_bf(ppaace->impl_attr, PAACE_IA_CID, stashid);
+
+ /* configure snoop id */
+ if (~snoopid != 0)
+ ppaace->domain_attr.to_host.snpid = snoopid;
+
+ if (subwin_cnt) {
+ /* The first entry is in the primary PAACE instead */
+ fspi = pamu_get_fspi_and_allocate(subwin_cnt - 1);
+ if (fspi == ULONG_MAX) {
+ pr_debug("spaace indexes exhausted\n");
+ return -EINVAL;
+ }
+
+ /* window count is 2^(WCE+1) bytes */
+ set_bf(ppaace->impl_attr, PAACE_IA_WCE,
+ map_subwindow_cnt_to_wce(subwin_cnt));
+ set_bf(ppaace->addr_bitfields, PPAACE_AF_MW, 0x1);
+ ppaace->fspi = fspi;
+ } else {
+ set_bf(ppaace->impl_attr, PAACE_IA_ATM, PAACE_ATM_WINDOW_XLATE);
+ ppaace->twbah = rpn >> 20;
+ set_bf(ppaace->win_bitfields, PAACE_WIN_TWBAL, rpn);
+ set_bf(ppaace->addr_bitfields, PAACE_AF_AP, prot);
+ set_bf(ppaace->impl_attr, PAACE_IA_WCE, 0);
+ set_bf(ppaace->addr_bitfields, PPAACE_AF_MW, 0);
+ }
+ mb();
+
+ return 0;
+}
+
+/**
+ * pamu_config_spaace() - Sets up SPAACE entry for specified subwindow
+ *
+ * @liodn: Logical IO device number
+ * @subwin_cnt: number of sub-windows associated with dma-window
+ * @subwin: subwindow index
+ * @subwin_size: size of subwindow
+ * @omi: Operation mapping index
+ * @rpn: real (true physical) page number
+ * @snoopid: snoop id for hardware coherency -- if ~snoopid == 0 then
+ * snoopid not defined
+ * @stashid: cache stash id for associated cpu
+ * @enable: enable/disable subwindow after reconfiguration
+ * @prot: sub window permissions
+ *
+ * Returns 0 upon success else error code < 0 returned
+ */
+int pamu_config_spaace(int liodn, u32 subwin_cnt, u32 subwin,
+ phys_addr_t subwin_size, u32 omi, unsigned long rpn,
+ u32 snoopid, u32 stashid, int enable, int prot)
+{
+ struct paace *paace;
+
+
+ /* setup sub-windows */
+ if (!subwin_cnt) {
+ pr_debug("Invalid subwindow count\n");
+ return -EINVAL;
+ }
+
+ paace = pamu_get_ppaace(liodn);
+ if (subwin > 0 && subwin < subwin_cnt && paace) {
+ paace = pamu_get_spaace(paace, subwin - 1);
+
+ if (paace && !(paace->addr_bitfields & PAACE_V_VALID)) {
+ pamu_init_spaace(paace);
+ set_bf(paace->addr_bitfields, SPAACE_AF_LIODN, liodn);
+ }
+ }
+
+ if (!paace) {
+ pr_debug("Invalid liodn entry\n");
+ return -ENOENT;
+ }
+
+ if (!is_power_of_2(subwin_size) || subwin_size < PAMU_PAGE_SIZE) {
+ pr_debug("subwindow size out of range, or not a power of 2\n");
+ return -EINVAL;
+ }
+
+ if (rpn == ULONG_MAX) {
+ pr_debug("real page number out of range\n");
+ return -EINVAL;
+ }
+
+ /* window size is 2^(WSE+1) bytes */
+ set_bf(paace->win_bitfields, PAACE_WIN_SWSE,
+ map_addrspace_size_to_wse(subwin_size));
+
+ set_bf(paace->impl_attr, PAACE_IA_ATM, PAACE_ATM_WINDOW_XLATE);
+ paace->twbah = rpn >> 20;
+ set_bf(paace->win_bitfields, PAACE_WIN_TWBAL, rpn);
+ set_bf(paace->addr_bitfields, PAACE_AF_AP, prot);
+
+ /* configure snoop id */
+ if (~snoopid != 0)
+ paace->domain_attr.to_host.snpid = snoopid;
+
+ /* set up operation mapping if it's configured */
+ if (omi < OME_NUMBER_ENTRIES) {
+ set_bf(paace->impl_attr, PAACE_IA_OTM, PAACE_OTM_INDEXED);
+ paace->op_encode.index_ot.omi = omi;
+ } else if (~omi != 0) {
+ pr_debug("bad operation mapping index: %d\n", omi);
+ return -EINVAL;
+ }
+
+ if (~stashid != 0)
+ set_bf(paace->impl_attr, PAACE_IA_CID, stashid);
+
+ smp_wmb();
+
+ if (enable)
+ set_bf(paace->addr_bitfields, PAACE_AF_V, PAACE_V_VALID);
+
+ mb();
+
+ return 0;
+}
+
+/**
+* get_ome_index() - Returns the index in the operation mapping table
+* for device.
+* @*omi_index: pointer for storing the index value
+*
+*/
+void get_ome_index(u32 *omi_index, struct device *dev)
+{
+ if (of_device_is_compatible(dev->of_node, "fsl,qman-portal"))
+ *omi_index = OMI_QMAN;
+ if (of_device_is_compatible(dev->of_node, "fsl,qman"))
+ *omi_index = OMI_QMAN_PRIV;
+}
+
+/**
+ * get_stash_id - Returns stash destination id corresponding to a
+ * cache type and vcpu.
+ * @stash_dest_hint: L1, L2 or L3
+ * @vcpu: vpcu target for a particular cache type.
+ *
+ * Returs stash on success or ~(u32)0 on failure.
+ *
+ */
+u32 get_stash_id(u32 stash_dest_hint, u32 vcpu)
+{
+ const u32 *prop;
+ struct device_node *node;
+ u32 cache_level;
+ int len, found = 0;
+ int i;
+
+ /* Fastpath, exit early if L3/CPC cache is target for stashing */
+ if (stash_dest_hint == PAMU_ATTR_CACHE_L3) {
+ node = of_find_matching_node(NULL, l3_device_ids);
+ if (node) {
+ prop = of_get_property(node, "cache-stash-id", 0);
+ if (!prop) {
+ pr_debug("missing cache-stash-id at %s\n", node->full_name);
+ of_node_put(node);
+ return ~(u32)0;
+ }
+ of_node_put(node);
+ return be32_to_cpup(prop);
+ }
+ return ~(u32)0;
+ }
+
+ for_each_node_by_type(node, "cpu") {
+ prop = of_get_property(node, "reg", &len);
+ for (i = 0; i < len / sizeof(u32); i++) {
+ if (be32_to_cpup(&prop[i]) == vcpu) {
+ found = 1;
+ goto found_cpu_node;
+ }
+ }
+ }
+found_cpu_node:
+
+ /* find the hwnode that represents the cache */
+ for (cache_level = PAMU_ATTR_CACHE_L1; (cache_level < PAMU_ATTR_CACHE_L3) && found; cache_level++) {
+ if (stash_dest_hint == cache_level) {
+ prop = of_get_property(node, "cache-stash-id", 0);
+ if (!prop) {
+ pr_debug("missing cache-stash-id at %s\n", node->full_name);
+ of_node_put(node);
+ return ~(u32)0;
+ }
+ of_node_put(node);
+ return be32_to_cpup(prop);
+ }
+
+ prop = of_get_property(node, "next-level-cache", 0);
+ if (!prop) {
+ pr_debug("can't find next-level-cache at %s\n",
+ node->full_name);
+ of_node_put(node);
+ return ~(u32)0; /* can't traverse any further */
+ }
+ of_node_put(node);
+
+ /* advance to next node in cache hierarchy */
+ node = of_find_node_by_phandle(*prop);
+ if (!node) {
+ pr_debug("Invalid node for cache hierarchy %s\n",
+ node->full_name);
+ return ~(u32)0;
+ }
+ }
+
+ pr_debug("stash dest not found for %d on vcpu %d\n",
+ stash_dest_hint, vcpu);
+ return ~(u32)0;
+}
+
+/* Identify if the PAACT table entry belongs to QMAN, BMAN or QMAN Portal */
+#define QMAN_PAACE 1
+#define QMAN_PORTAL_PAACE 2
+#define BMAN_PAACE 3
+
+/**
+ * Setup operation mapping and stash destinations for QMAN and QMAN portal.
+ * Memory accesses to QMAN and BMAN private memory need not be coherent, so
+ * clear the PAACE entry coherency attribute for them.
+ */
+static void setup_qbman_paace(struct paace *ppaace, int paace_type)
+{
+ switch (paace_type) {
+ case QMAN_PAACE:
+ set_bf(ppaace->impl_attr, PAACE_IA_OTM, PAACE_OTM_INDEXED);
+ ppaace->op_encode.index_ot.omi = OMI_QMAN_PRIV;
+ /* setup QMAN Private data stashing for the L3 cache */
+ set_bf(ppaace->impl_attr, PAACE_IA_CID, get_stash_id(PAMU_ATTR_CACHE_L3, 0));
+ set_bf(ppaace->domain_attr.to_host.coherency_required, PAACE_DA_HOST_CR,
+ 0);
+ break;
+ case QMAN_PORTAL_PAACE:
+ set_bf(ppaace->impl_attr, PAACE_IA_OTM, PAACE_OTM_INDEXED);
+ ppaace->op_encode.index_ot.omi = OMI_QMAN;
+ /*Set DQRR and Frame stashing for the L3 cache */
+ set_bf(ppaace->impl_attr, PAACE_IA_CID, get_stash_id(PAMU_ATTR_CACHE_L3, 0));
+ break;
+ case BMAN_PAACE:
+ set_bf(ppaace->domain_attr.to_host.coherency_required, PAACE_DA_HOST_CR,
+ 0);
+ break;
+ }
+}
+
+/**
+ * Setup the operation mapping table for various devices. This is a static
+ * table where each table index corresponds to a particular device. PAMU uses
+ * this table to translate device transaction to appropriate corenet
+ * transaction.
+ */
+static void __init setup_omt(struct ome *omt)
+{
+ struct ome *ome;
+
+ /* Configure OMI_QMAN */
+ ome = &omt[OMI_QMAN];
+
+ ome->moe[IOE_READ_IDX] = EOE_VALID | EOE_READ;
+ ome->moe[IOE_EREAD0_IDX] = EOE_VALID | EOE_RSA;
+ ome->moe[IOE_WRITE_IDX] = EOE_VALID | EOE_WRITE;
+ ome->moe[IOE_EWRITE0_IDX] = EOE_VALID | EOE_WWSAO;
+
+ ome->moe[IOE_DIRECT0_IDX] = EOE_VALID | EOE_LDEC;
+ ome->moe[IOE_DIRECT1_IDX] = EOE_VALID | EOE_LDECPE;
+
+ /* Configure OMI_FMAN */
+ ome = &omt[OMI_FMAN];
+ ome->moe[IOE_READ_IDX] = EOE_VALID | EOE_READI;
+ ome->moe[IOE_WRITE_IDX] = EOE_VALID | EOE_WRITE;
+
+ /* Configure OMI_QMAN private */
+ ome = &omt[OMI_QMAN_PRIV];
+ ome->moe[IOE_READ_IDX] = EOE_VALID | EOE_READ;
+ ome->moe[IOE_WRITE_IDX] = EOE_VALID | EOE_WRITE;
+ ome->moe[IOE_EREAD0_IDX] = EOE_VALID | EOE_RSA;
+ ome->moe[IOE_EWRITE0_IDX] = EOE_VALID | EOE_WWSA;
+
+ /* Configure OMI_CAAM */
+ ome = &omt[OMI_CAAM];
+ ome->moe[IOE_READ_IDX] = EOE_VALID | EOE_READI;
+ ome->moe[IOE_WRITE_IDX] = EOE_VALID | EOE_WRITE;
+}
+
+/*
+ * Get the maximum number of PAACT table entries
+ * and subwindows supported by PAMU
+ */
+static void get_pamu_cap_values(unsigned long pamu_reg_base)
+{
+ u32 pc_val;
+
+ pc_val = in_be32((u32 *)(pamu_reg_base + PAMU_PC3));
+ /* Maximum number of subwindows per liodn */
+ max_subwindow_count = 1 << (1 + PAMU_PC3_MWCE(pc_val));
+}
+
+/* Setup PAMU registers pointing to PAACT, SPAACT and OMT */
+int setup_one_pamu(unsigned long pamu_reg_base, unsigned long pamu_reg_size,
+ phys_addr_t ppaact_phys, phys_addr_t spaact_phys,
+ phys_addr_t omt_phys)
+{
+ u32 *pc;
+ struct pamu_mmap_regs *pamu_regs;
+
+ pc = (u32 *) (pamu_reg_base + PAMU_PC);
+ pamu_regs = (struct pamu_mmap_regs *)
+ (pamu_reg_base + PAMU_MMAP_REGS_BASE);
+
+ /* set up pointers to corenet control blocks */
+
+ out_be32(&pamu_regs->ppbah, upper_32_bits(ppaact_phys));
+ out_be32(&pamu_regs->ppbal, lower_32_bits(ppaact_phys));
+ ppaact_phys = ppaact_phys + PAACT_SIZE;
+ out_be32(&pamu_regs->pplah, upper_32_bits(ppaact_phys));
+ out_be32(&pamu_regs->pplal, lower_32_bits(ppaact_phys));
+
+ out_be32(&pamu_regs->spbah, upper_32_bits(spaact_phys));
+ out_be32(&pamu_regs->spbal, lower_32_bits(spaact_phys));
+ spaact_phys = spaact_phys + SPAACT_SIZE;
+ out_be32(&pamu_regs->splah, upper_32_bits(spaact_phys));
+ out_be32(&pamu_regs->splal, lower_32_bits(spaact_phys));
+
+ out_be32(&pamu_regs->obah, upper_32_bits(omt_phys));
+ out_be32(&pamu_regs->obal, lower_32_bits(omt_phys));
+ omt_phys = omt_phys + OMT_SIZE;
+ out_be32(&pamu_regs->olah, upper_32_bits(omt_phys));
+ out_be32(&pamu_regs->olal, lower_32_bits(omt_phys));
+
+ /*
+ * set PAMU enable bit,
+ * allow ppaact & omt to be cached
+ * & enable PAMU access violation interrupts.
+ */
+
+ out_be32((u32 *)(pamu_reg_base + PAMU_PICS),
+ PAMU_ACCESS_VIOLATION_ENABLE);
+ out_be32(pc, PAMU_PC_PE | PAMU_PC_OCE | PAMU_PC_SPCC | PAMU_PC_PPCC);
+ return 0;
+}
+
+/* Enable all device LIODNS */
+static void __init setup_liodns(void)
+{
+ int i, len;
+ struct paace *ppaace;
+ struct device_node *node = NULL;
+ const u32 *prop;
+
+ for_each_node_with_property(node, "fsl,liodn") {
+ prop = of_get_property(node, "fsl,liodn", &len);
+ for (i = 0; i < len / sizeof(u32); i++) {
+ int liodn;
+
+ liodn = be32_to_cpup(&prop[i]);
+ if (liodn >= PAACE_NUMBER_ENTRIES) {
+ pr_debug("Invalid LIODN value %d\n", liodn);
+ continue;
+ }
+ ppaace = pamu_get_ppaace(liodn);
+ pamu_init_ppaace(ppaace);
+ /* window size is 2^(WSE+1) bytes */
+ set_bf(ppaace->addr_bitfields, PPAACE_AF_WSE, 35);
+ ppaace->wbah = 0;
+ set_bf(ppaace->addr_bitfields, PPAACE_AF_WBAL, 0);
+ set_bf(ppaace->impl_attr, PAACE_IA_ATM,
+ PAACE_ATM_NO_XLATE);
+ set_bf(ppaace->addr_bitfields, PAACE_AF_AP,
+ PAACE_AP_PERMS_ALL);
+ if (of_device_is_compatible(node, "fsl,qman-portal"))
+ setup_qbman_paace(ppaace, QMAN_PORTAL_PAACE);
+ if (of_device_is_compatible(node, "fsl,qman"))
+ setup_qbman_paace(ppaace, QMAN_PAACE);
+ if (of_device_is_compatible(node, "fsl,bman"))
+ setup_qbman_paace(ppaace, BMAN_PAACE);
+ mb();
+ pamu_enable_liodn(liodn);
+ }
+ }
+}
+
+irqreturn_t pamu_av_isr(int irq, void *arg)
+{
+ struct pamu_isr_data *data = arg;
+ phys_addr_t phys;
+ unsigned int i, j, ret;
+
+ pr_emerg("fsl-pamu: access violation interrupt\n");
+
+ for (i = 0; i < data->count; i++) {
+ void __iomem *p = data->pamu_reg_base + i * PAMU_OFFSET;
+ u32 pics = in_be32(p + PAMU_PICS);
+
+ if (pics & PAMU_ACCESS_VIOLATION_STAT) {
+ u32 avs1 = in_be32(p + PAMU_AVS1);
+ struct paace *paace;
+
+ pr_emerg("POES1=%08x\n", in_be32(p + PAMU_POES1));
+ pr_emerg("POES2=%08x\n", in_be32(p + PAMU_POES2));
+ pr_emerg("AVS1=%08x\n", avs1);
+ pr_emerg("AVS2=%08x\n", in_be32(p + PAMU_AVS2));
+ pr_emerg("AVA=%016llx\n", make64(in_be32(p + PAMU_AVAH),
+ in_be32(p + PAMU_AVAL)));
+ pr_emerg("UDAD=%08x\n", in_be32(p + PAMU_UDAD));
+ pr_emerg("POEA=%016llx\n", make64(in_be32(p + PAMU_POEAH),
+ in_be32(p + PAMU_POEAL)));
+
+ phys = make64(in_be32(p + PAMU_POEAH),
+ in_be32(p + PAMU_POEAL));
+
+ /* Assume that POEA points to a PAACE */
+ if (phys) {
+ u32 *paace = phys_to_virt(phys);
+
+ /* Only the first four words are relevant */
+ for (j = 0; j < 4; j++)
+ pr_emerg("PAACE[%u]=%08x\n", j, in_be32(paace + j));
+ }
+
+ /* clear access violation condition */
+ out_be32((p + PAMU_AVS1), avs1 & PAMU_AV_MASK);
+ paace = pamu_get_ppaace(avs1 >> PAMU_AVS1_LIODN_SHIFT);
+ BUG_ON(!paace);
+ /* check if we got a violation for a disabled LIODN */
+ if (!get_bf(paace->addr_bitfields, PAACE_AF_V)) {
+ /*
+ * As per hardware erratum A-003638, access
+ * violation can be reported for a disabled
+ * LIODN. If we hit that condition, disable
+ * access violation reporting.
+ */
+ pics &= ~PAMU_ACCESS_VIOLATION_ENABLE;
+ } else {
+ /* Disable the LIODN */
+ ret = pamu_disable_liodn(avs1 >> PAMU_AVS1_LIODN_SHIFT);
+ BUG_ON(ret);
+ pr_emerg("Disabling liodn %x\n", avs1 >> PAMU_AVS1_LIODN_SHIFT);
+ }
+ out_be32((p + PAMU_PICS), pics);
+ }
+ }
+
+
+ return IRQ_HANDLED;
+}
+
+#define LAWAR_EN 0x80000000
+#define LAWAR_TARGET_MASK 0x0FF00000
+#define LAWAR_TARGET_SHIFT 20
+#define LAWAR_SIZE_MASK 0x0000003F
+#define LAWAR_CSDID_MASK 0x000FF000
+#define LAWAR_CSDID_SHIFT 12
+
+#define LAW_SIZE_4K 0xb
+
+struct ccsr_law {
+ u32 lawbarh; /* LAWn base address high */
+ u32 lawbarl; /* LAWn base address low */
+ u32 lawar; /* LAWn attributes */
+ u32 reserved;
+};
+
+/*
+ * Create a coherence subdomain for a given memory block.
+ */
+static int __init create_csd(phys_addr_t phys, size_t size, u32 csd_port_id)
+{
+ struct device_node *np;
+ const __be32 *iprop;
+ void __iomem *lac = NULL; /* Local Access Control registers */
+ struct ccsr_law __iomem *law;
+ void __iomem *ccm = NULL;
+ u32 __iomem *csdids;
+ unsigned int i, num_laws, num_csds;
+ u32 law_target = 0;
+ u32 csd_id = 0;
+ int ret = 0;
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,corenet-law");
+ if (!np)
+ return -ENODEV;
+
+ iprop = of_get_property(np, "fsl,num-laws", NULL);
+ if (!iprop) {
+ ret = -ENODEV;
+ goto error;
+ }
+
+ num_laws = be32_to_cpup(iprop);
+ if (!num_laws) {
+ ret = -ENODEV;
+ goto error;
+ }
+
+ lac = of_iomap(np, 0);
+ if (!lac) {
+ ret = -ENODEV;
+ goto error;
+ }
+
+ /* LAW registers are at offset 0xC00 */
+ law = lac + 0xC00;
+
+ of_node_put(np);
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,corenet-cf");
+ if (!np) {
+ ret = -ENODEV;
+ goto error;
+ }
+
+ iprop = of_get_property(np, "fsl,ccf-num-csdids", NULL);
+ if (!iprop) {
+ ret = -ENODEV;
+ goto error;
+ }
+
+ num_csds = be32_to_cpup(iprop);
+ if (!num_csds) {
+ ret = -ENODEV;
+ goto error;
+ }
+
+ ccm = of_iomap(np, 0);
+ if (!ccm) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ /* The undocumented CSDID registers are at offset 0x600 */
+ csdids = ccm + 0x600;
+
+ of_node_put(np);
+ np = NULL;
+
+ /* Find an unused coherence subdomain ID */
+ for (csd_id = 0; csd_id < num_csds; csd_id++) {
+ if (!csdids[csd_id])
+ break;
+ }
+
+ /* Store the Port ID in the (undocumented) proper CIDMRxx register */
+ csdids[csd_id] = csd_port_id;
+
+ /* Find the DDR LAW that maps to our buffer. */
+ for (i = 0; i < num_laws; i++) {
+ if (law[i].lawar & LAWAR_EN) {
+ phys_addr_t law_start, law_end;
+
+ law_start = make64(law[i].lawbarh, law[i].lawbarl);
+ law_end = law_start +
+ (2ULL << (law[i].lawar & LAWAR_SIZE_MASK));
+
+ if (law_start <= phys && phys < law_end) {
+ law_target = law[i].lawar & LAWAR_TARGET_MASK;
+ break;
+ }
+ }
+ }
+
+ if (i == 0 || i == num_laws) {
+ /* This should never happen*/
+ ret = -ENOENT;
+ goto error;
+ }
+
+ /* Find a free LAW entry */
+ while (law[--i].lawar & LAWAR_EN) {
+ if (i == 0) {
+ /* No higher priority LAW slots available */
+ ret = -ENOENT;
+ goto error;
+ }
+ }
+
+ law[i].lawbarh = upper_32_bits(phys);
+ law[i].lawbarl = lower_32_bits(phys);
+ wmb();
+ law[i].lawar = LAWAR_EN | law_target | (csd_id << LAWAR_CSDID_SHIFT) |
+ (LAW_SIZE_4K + get_order(size));
+ wmb();
+
+error:
+ if (ccm)
+ iounmap(ccm);
+
+ if (lac)
+ iounmap(lac);
+
+ if (np)
+ of_node_put(np);
+
+ return ret;
+}
+
+/*
+ * Table of SVRs and the corresponding PORT_ID values. Port ID corresponds to a
+ * bit map of snoopers for a given range of memory mapped by a LAW.
+ *
+ * All future CoreNet-enabled SOCs will have this erratum(A-004510) fixed, so this
+ * table should never need to be updated. SVRs are guaranteed to be unique, so
+ * there is no worry that a future SOC will inadvertently have one of these
+ * values.
+ */
+static const struct {
+ u32 svr;
+ u32 port_id;
+} port_id_map[] = {
+ {0x82100010, 0xFF000000}, /* P2040 1.0 */
+ {0x82100011, 0xFF000000}, /* P2040 1.1 */
+ {0x82100110, 0xFF000000}, /* P2041 1.0 */
+ {0x82100111, 0xFF000000}, /* P2041 1.1 */
+ {0x82110310, 0xFF000000}, /* P3041 1.0 */
+ {0x82110311, 0xFF000000}, /* P3041 1.1 */
+ {0x82010020, 0xFFF80000}, /* P4040 2.0 */
+ {0x82000020, 0xFFF80000}, /* P4080 2.0 */
+ {0x82210010, 0xFC000000}, /* P5010 1.0 */
+ {0x82210020, 0xFC000000}, /* P5010 2.0 */
+ {0x82200010, 0xFC000000}, /* P5020 1.0 */
+ {0x82050010, 0xFF800000}, /* P5021 1.0 */
+ {0x82040010, 0xFF800000}, /* P5040 1.0 */
+};
+
+#define SVR_SECURITY 0x80000 /* The Security (E) bit */
+
+static int __init fsl_pamu_probe(struct platform_device *pdev)
+{
+ void __iomem *pamu_regs = NULL;
+ struct ccsr_guts __iomem *guts_regs = NULL;
+ u32 pamubypenr, pamu_counter;
+ unsigned long pamu_reg_off;
+ unsigned long pamu_reg_base;
+ struct pamu_isr_data *data = NULL;
+ struct device_node *guts_node;
+ u64 size;
+ struct page *p;
+ int ret = 0;
+ int irq;
+ phys_addr_t ppaact_phys;
+ phys_addr_t spaact_phys;
+ phys_addr_t omt_phys;
+ size_t mem_size = 0;
+ unsigned int order = 0;
+ u32 csd_port_id = 0;
+ unsigned i;
+ /*
+ * enumerate all PAMUs and allocate and setup PAMU tables
+ * for each of them,
+ * NOTE : All PAMUs share the same LIODN tables.
+ */
+
+ pamu_regs = of_iomap(pdev->dev.of_node, 0);
+ if (!pamu_regs) {
+ dev_err(&pdev->dev, "ioremap of PAMU node failed\n");
+ return -ENOMEM;
+ }
+ of_get_address(pdev->dev.of_node, 0, &size, NULL);
+
+ irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
+ if (irq == NO_IRQ) {
+ dev_warn(&pdev->dev, "no interrupts listed in PAMU node\n");
+ goto error;
+ }
+
+ data = kzalloc(sizeof(struct pamu_isr_data), GFP_KERNEL);
+ if (!data) {
+ dev_err(&pdev->dev, "PAMU isr data memory allocation failed\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+ data->pamu_reg_base = pamu_regs;
+ data->count = size / PAMU_OFFSET;
+
+ /* The ISR needs access to the regs, so we won't iounmap them */
+ ret = request_irq(irq, pamu_av_isr, 0, "pamu", data);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "error %i installing ISR for irq %i\n",
+ ret, irq);
+ goto error;
+ }
+
+ guts_node = of_find_matching_node(NULL, guts_device_ids);
+ if (!guts_node) {
+ dev_err(&pdev->dev, "could not find GUTS node %s\n",
+ pdev->dev.of_node->full_name);
+ ret = -ENODEV;
+ goto error;
+ }
+
+ guts_regs = of_iomap(guts_node, 0);
+ of_node_put(guts_node);
+ if (!guts_regs) {
+ dev_err(&pdev->dev, "ioremap of GUTS node failed\n");
+ ret = -ENODEV;
+ goto error;
+ }
+
+ /* read in the PAMU capability registers */
+ get_pamu_cap_values((unsigned long)pamu_regs);
+ /*
+ * To simplify the allocation of a coherency domain, we allocate the
+ * PAACT and the OMT in the same memory buffer. Unfortunately, this
+ * wastes more memory compared to allocating the buffers separately.
+ */
+ /* Determine how much memory we need */
+ mem_size = (PAGE_SIZE << get_order(PAACT_SIZE)) +
+ (PAGE_SIZE << get_order(SPAACT_SIZE)) +
+ (PAGE_SIZE << get_order(OMT_SIZE));
+ order = get_order(mem_size);
+
+ p = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
+ if (!p) {
+ dev_err(&pdev->dev, "unable to allocate PAACT/SPAACT/OMT block\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ ppaact = page_address(p);
+ ppaact_phys = page_to_phys(p);
+
+ /* Make sure the memory is naturally aligned */
+ if (ppaact_phys & ((PAGE_SIZE << order) - 1)) {
+ dev_err(&pdev->dev, "PAACT/OMT block is unaligned\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ spaact = (void *)ppaact + (PAGE_SIZE << get_order(PAACT_SIZE));
+ omt = (void *)spaact + (PAGE_SIZE << get_order(SPAACT_SIZE));
+
+ dev_dbg(&pdev->dev, "ppaact virt=%p phys=0x%llx\n", ppaact,
+ (unsigned long long) ppaact_phys);
+
+ /* Check to see if we need to implement the work-around on this SOC */
+
+ /* Determine the Port ID for our coherence subdomain */
+ for (i = 0; i < ARRAY_SIZE(port_id_map); i++) {
+ if (port_id_map[i].svr == (mfspr(SPRN_SVR) & ~SVR_SECURITY)) {
+ csd_port_id = port_id_map[i].port_id;
+ dev_dbg(&pdev->dev, "found matching SVR %08x\n",
+ port_id_map[i].svr);
+ break;
+ }
+ }
+
+ if (csd_port_id) {
+ dev_dbg(&pdev->dev, "creating coherency subdomain at address "
+ "0x%llx, size %zu, port id 0x%08x", ppaact_phys,
+ mem_size, csd_port_id);
+
+ ret = create_csd(ppaact_phys, mem_size, csd_port_id);
+ if (ret) {
+ dev_err(&pdev->dev, "could not create coherence "
+ "subdomain\n");
+ return ret;
+ }
+ }
+
+ spaact_phys = virt_to_phys(spaact);
+ omt_phys = virt_to_phys(omt);
+
+ spaace_pool = gen_pool_create(ilog2(sizeof(struct paace)), -1);
+ if (!spaace_pool) {
+ ret = -ENOMEM;
+ dev_err(&pdev->dev, "PAMU : failed to allocate spaace gen pool\n");
+ goto error;
+ }
+
+ ret = gen_pool_add(spaace_pool, (unsigned long)spaact, SPAACT_SIZE, -1);
+ if (ret)
+ goto error_genpool;
+
+ pamubypenr = in_be32(&guts_regs->pamubypenr);
+
+ for (pamu_reg_off = 0, pamu_counter = 0x80000000; pamu_reg_off < size;
+ pamu_reg_off += PAMU_OFFSET, pamu_counter >>= 1) {
+
+ pamu_reg_base = (unsigned long) pamu_regs + pamu_reg_off;
+ setup_one_pamu(pamu_reg_base, pamu_reg_off, ppaact_phys,
+ spaact_phys, omt_phys);
+ /* Disable PAMU bypass for this PAMU */
+ pamubypenr &= ~pamu_counter;
+ }
+
+ setup_omt(omt);
+
+ /* Enable all relevant PAMU(s) */
+ out_be32(&guts_regs->pamubypenr, pamubypenr);
+
+ iounmap(guts_regs);
+
+ /* Enable DMA for the LIODNs in the device tree*/
+
+ setup_liodns();
+
+ return 0;
+
+error_genpool:
+ gen_pool_destroy(spaace_pool);
+
+error:
+ if (irq != NO_IRQ)
+ free_irq(irq, data);
+
+ if (data) {
+ memset(data, 0, sizeof(struct pamu_isr_data));
+ kfree(data);
+ }
+
+ if (pamu_regs)
+ iounmap(pamu_regs);
+
+ if (guts_regs)
+ iounmap(guts_regs);
+
+ if (ppaact)
+ free_pages((unsigned long)ppaact, order);
+
+ ppaact = NULL;
+
+ return ret;
+}
+
+static const struct of_device_id fsl_of_pamu_ids[] = {
+ {
+ .compatible = "fsl,p4080-pamu",
+ },
+ {
+ .compatible = "fsl,pamu",
+ },
+ {},
+};
+
+static struct platform_driver fsl_of_pamu_driver = {
+ .driver = {
+ .name = "fsl-of-pamu",
+ .owner = THIS_MODULE,
+ },
+ .probe = fsl_pamu_probe,
+};
+
+static __init int fsl_pamu_init(void)
+{
+ struct platform_device *pdev = NULL;
+ struct device_node *np;
+ int ret;
+
+ /*
+ * The normal OF process calls the probe function at some
+ * indeterminate later time, after most drivers have loaded. This is
+ * too late for us, because PAMU clients (like the Qman driver)
+ * depend on PAMU being initialized early.
+ *
+ * So instead, we "manually" call our probe function by creating the
+ * platform devices ourselves.
+ */
+
+ /*
+ * We assume that there is only one PAMU node in the device tree. A
+ * single PAMU node represents all of the PAMU devices in the SOC
+ * already. Everything else already makes that assumption, and the
+ * binding for the PAMU nodes doesn't allow for any parent-child
+ * relationships anyway. In other words, support for more than one
+ * PAMU node would require significant changes to a lot of code.
+ */
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,pamu");
+ if (!np) {
+ pr_err("fsl-pamu: could not find a PAMU node\n");
+ return -ENODEV;
+ }
+
+ ret = platform_driver_register(&fsl_of_pamu_driver);
+ if (ret) {
+ pr_err("fsl-pamu: could not register driver (err=%i)\n", ret);
+ goto error_driver_register;
+ }
+
+ pdev = platform_device_alloc("fsl-of-pamu", 0);
+ if (!pdev) {
+ pr_err("fsl-pamu: could not allocate device %s\n",
+ np->full_name);
+ ret = -ENOMEM;
+ goto error_device_alloc;
+ }
+ pdev->dev.of_node = of_node_get(np);
+
+ ret = pamu_domain_init();
+ if (ret)
+ goto error_device_add;
+
+ ret = platform_device_add(pdev);
+ if (ret) {
+ pr_err("fsl-pamu: could not add device %s (err=%i)\n",
+ np->full_name, ret);
+ goto error_device_add;
+ }
+
+ return 0;
+
+error_device_add:
+ of_node_put(pdev->dev.of_node);
+ pdev->dev.of_node = NULL;
+
+ platform_device_put(pdev);
+
+error_device_alloc:
+ platform_driver_unregister(&fsl_of_pamu_driver);
+
+error_driver_register:
+ of_node_put(np);
+
+ return ret;
+}
+arch_initcall(fsl_pamu_init);