gpu: nvgpu: refectored sim_readl/sim_writel

refactored sim_readl and sim_writel to use
os-agnostic structures.

converted all sim buffers to the type nvgpu_mem and
replaced all alloc_page and free_page calls with
corresponding nvgpu_dma_alloc/nvgpu_dma_free calls.

JIRA VQRM-2368

Change-Id: Ia9d29119d31f239ed16be932cfd16c334002c727
Signed-off-by: Antony Clince Alex <aalex@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1702050
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: Sourab Gupta <sourabg@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

3 files changed, 168 insertions, 187 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/sim.c b/drivers/gpu/nvgpu/common/linux/sim.c
index 0e158063..7ab7a153 100644
--- a/drivers/gpu/nvgpu/common/linux/sim.c
+++ b/drivers/gpu/nvgpu/common/linux/sim.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -20,47 +20,67 @@
 
 #include <nvgpu/log.h>
 #include <nvgpu/linux/vm.h>
-
+#include <nvgpu/bitops.h>
+#include <nvgpu/nvgpu_mem.h>
+#include <nvgpu/dma.h>
 #include "gk20a/gk20a.h"
 #include "sim.h"
 
 #include <nvgpu/hw/gk20a/hw_sim_gk20a.h>
 
-static inline void sim_writel(struct sim_gk20a_linux *sim_linux, u32 r, u32 v)
+static inline void sim_writel(struct sim_gk20a *sim, u32 r, u32 v)
 {
+        struct sim_gk20a_linux *sim_linux =
+                container_of(sim, struct sim_gk20a_linux, sim);
+
         writel(v, sim_linux->regs + r);
 }
 
-static inline u32 sim_readl(struct sim_gk20a_linux *sim_linux, u32 r)
+static inline u32 sim_readl(struct sim_gk20a *sim, u32 r)
 {
+        struct sim_gk20a_linux *sim_linux =
+                container_of(sim, struct sim_gk20a_linux, sim);
+
         return readl(sim_linux->regs + r);
 }
 
-static void kunmap_and_free_iopage(void **kvaddr, struct page **page)
+static int gk20a_alloc_sim_buffer(struct gk20a *g, struct nvgpu_mem *mem)
 {
-        if (*kvaddr) {
-                kunmap(*kvaddr);
-                *kvaddr = NULL;
-        }
-        if (*page) {
-                __free_page(*page);
-                *page = NULL;
+        int err;
+
+        err = nvgpu_dma_alloc(g, PAGE_SIZE, mem);
+
+        if (err)
+                return err;
+        /*
+         * create a valid cpu_va mapping
+         */
+        nvgpu_mem_begin(g, mem);
+
+        return 0;
+}
+
+static void gk20a_free_sim_buffer(struct gk20a *g, struct nvgpu_mem *mem)
+{
+        if (nvgpu_mem_is_valid(mem)) {
+                /*
+                 * invalidate the cpu_va mapping
+                 */
+                nvgpu_mem_end(g, mem);
+                nvgpu_dma_free(g, mem);
         }
+
+        memset(mem, 0, sizeof(*mem));
 }
 
 static void gk20a_free_sim_support(struct gk20a *g)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        /* free sim mappings, bfrs */
-        kunmap_and_free_iopage(&sim_linux->send_bfr.kvaddr,
-                               &sim_linux->send_bfr.page);
 
-        kunmap_and_free_iopage(&sim_linux->recv_bfr.kvaddr,
-                               &sim_linux->recv_bfr.page);
-
-        kunmap_and_free_iopage(&sim_linux->msg_bfr.kvaddr,
-                               &sim_linux->msg_bfr.page);
+        gk20a_free_sim_buffer(g, &sim_linux->send_bfr);
+        gk20a_free_sim_buffer(g, &sim_linux->recv_bfr);
+        gk20a_free_sim_buffer(g, &sim_linux->msg_bfr);
 }
 
 static void gk20a_remove_sim_support(struct sim_gk20a *s)
@@ -70,7 +90,7 @@ static void gk20a_remove_sim_support(struct sim_gk20a *s)
                 container_of(g->sim, struct sim_gk20a_linux, sim);
 
         if (sim_linux->regs)
-                sim_writel(sim_linux, sim_config_r(), sim_config_mode_disabled_v());
+                sim_writel(s, sim_config_r(), sim_config_mode_disabled_v());
         gk20a_free_sim_support(g);
 
         if (sim_linux->regs) {
@@ -82,35 +102,6 @@ static void gk20a_remove_sim_support(struct sim_gk20a *s)
         g->sim = NULL;
 }
 
-static int alloc_and_kmap_iopage(struct gk20a *g,
-                                 void **kvaddr,
-                                 u64 *phys,
-                                 struct page **page)
-{
-        int err = 0;
-        *page = alloc_page(GFP_KERNEL);
-
-        if (!*page) {
-                err = -ENOMEM;
-                nvgpu_err(g, "couldn't allocate io page");
-                goto fail;
-        }
-
-        *kvaddr = kmap(*page);
-        if (!*kvaddr) {
-                err = -ENOMEM;
-                nvgpu_err(g, "couldn't kmap io page");
-                goto fail;
-        }
-        *phys = page_to_phys(*page);
-        return 0;
-
- fail:
-        kunmap_and_free_iopage(kvaddr, page);
-        return err;
-
-}
-
 static inline u32 sim_msg_header_size(void)
 {
         return 24;/*TBD: fix the header to gt this from NV_VGPU_MSG_HEADER*/
@@ -120,7 +111,11 @@ static inline u32 *sim_msg_bfr(struct gk20a *g, u32 byte_offset)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        return (u32 *)(sim_linux->msg_bfr.kvaddr + byte_offset);
+        u8 *cpu_va;
+
+        cpu_va = (u8 *)sim_linux->msg_bfr.cpu_va;
+
+        return (u32 *)(cpu_va + byte_offset);
 }
 
 static inline u32 *sim_msg_hdr(struct gk20a *g, u32 byte_offset)
@@ -153,7 +148,11 @@ static u32 *sim_send_ring_bfr(struct gk20a *g, u32 byte_offset)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        return (u32 *)(sim_linux->send_bfr.kvaddr + byte_offset);
+        u8 *cpu_va;
+
+        cpu_va = (u8 *)sim_linux->send_bfr.cpu_va;
+
+        return (u32 *)(cpu_va + byte_offset);
 }
 
 static int rpc_send_message(struct gk20a *g)
@@ -169,18 +168,17 @@ static int rpc_send_message(struct gk20a *g)
                 sim_dma_target_phys_pci_coherent_f() |
                 sim_dma_status_valid_f() |
                 sim_dma_size_4kb_f() |
-                sim_dma_addr_lo_f(sim_linux->msg_bfr.phys >> PAGE_SHIFT);
+                sim_dma_addr_lo_f(nvgpu_mem_get_addr(g, &sim_linux->msg_bfr) >> PAGE_SHIFT);
 
         *sim_send_ring_bfr(g, dma_hi_offset*sizeof(u32)) =
-                u64_hi32(sim_linux->msg_bfr.phys);
+                u64_hi32(nvgpu_mem_get_addr(g, &sim_linux->msg_bfr));
 
         *sim_msg_hdr(g, sim_msg_sequence_r()) = g->sim->sequence_base++;
 
-        g->sim->send_ring_put = (g->sim->send_ring_put + 2 * sizeof(u32)) %
-                PAGE_SIZE;
+        g->sim->send_ring_put = (g->sim->send_ring_put + 2 * sizeof(u32)) % PAGE_SIZE;
 
         /* Update the put pointer. This will trap into the host. */
-        sim_writel(sim_linux, sim_send_put_r(), g->sim->send_ring_put);
+        sim_writel(g->sim, sim_send_put_r(), g->sim->send_ring_put);
 
         return 0;
 }
@@ -189,7 +187,11 @@ static inline u32 *sim_recv_ring_bfr(struct gk20a *g, u32 byte_offset)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        return (u32 *)(sim_linux->recv_bfr.kvaddr + byte_offset);
+        u8 *cpu_va;
+
+        cpu_va = (u8 *)sim_linux->recv_bfr.cpu_va;
+
+        return (u32 *)(cpu_va + byte_offset);
 }
 
 static int rpc_recv_poll(struct gk20a *g)
@@ -203,7 +205,7 @@ static int rpc_recv_poll(struct gk20a *g)
 
         /* Poll the recv ring get pointer in an infinite loop*/
         do {
-                g->sim->recv_ring_put = sim_readl(sim_linux, sim_recv_put_r());
+                g->sim->recv_ring_put = sim_readl(g->sim, sim_recv_put_r());
         } while (g->sim->recv_ring_put == g->sim->recv_ring_get);
 
         /* process all replies */
@@ -220,19 +222,19 @@ static int rpc_recv_poll(struct gk20a *g)
                 recv_phys_addr = (u64)recv_phys_addr_hi << 32 |
                                  (u64)recv_phys_addr_lo << PAGE_SHIFT;
 
-                if (recv_phys_addr != sim_linux->msg_bfr.phys) {
+                if (recv_phys_addr !=
+                                nvgpu_mem_get_addr(g, &sim_linux->msg_bfr)) {
                         nvgpu_err(g, "%s Error in RPC reply",
                                 __func__);
                         return -1;
                 }
 
                 /* Update GET pointer */
-                g->sim->recv_ring_get = (g->sim->recv_ring_get + 2*sizeof(u32)) %
-                        PAGE_SIZE;
+                g->sim->recv_ring_get = (g->sim->recv_ring_get + 2*sizeof(u32)) % PAGE_SIZE;
 
-                sim_writel(sim_linux, sim_recv_get_r(), g->sim->recv_ring_get);
+                sim_writel(g->sim, sim_recv_get_r(), g->sim->recv_ring_get);
 
-                g->sim->recv_ring_put = sim_readl(sim_linux, sim_recv_put_r());
+                g->sim->recv_ring_put = sim_readl(g->sim, sim_recv_put_r());
         }
 
         return 0;
@@ -295,53 +297,41 @@ int gk20a_init_sim_support(struct gk20a *g)
                 container_of(g->sim, struct sim_gk20a_linux, sim);
 
         /* allocate sim event/msg buffers */
-        err = alloc_and_kmap_iopage(g, &sim_linux->send_bfr.kvaddr,
-                                    &sim_linux->send_bfr.phys,
-                                    &sim_linux->send_bfr.page);
-
-        err = err || alloc_and_kmap_iopage(g, &sim_linux->recv_bfr.kvaddr,
-                                           &sim_linux->recv_bfr.phys,
-                                           &sim_linux->recv_bfr.page);
-
-        err = err || alloc_and_kmap_iopage(g, &sim_linux->msg_bfr.kvaddr,
-                                           &sim_linux->msg_bfr.phys,
-                                           &sim_linux->msg_bfr.page);
+        err = gk20a_alloc_sim_buffer(g, &sim_linux->send_bfr);
+        err = err || gk20a_alloc_sim_buffer(g, &sim_linux->recv_bfr);
+        err = err || gk20a_alloc_sim_buffer(g, &sim_linux->msg_bfr);
 
-        if (!(sim_linux->send_bfr.kvaddr && sim_linux->recv_bfr.kvaddr &&
-              sim_linux->msg_bfr.kvaddr)) {
-                nvgpu_err(g, "couldn't allocate all sim buffers");
+        if (err)
                 goto fail;
-        }
-
         /*mark send ring invalid*/
-        sim_writel(sim_linux, sim_send_ring_r(), sim_send_ring_status_invalid_f());
+        sim_writel(g->sim, sim_send_ring_r(), sim_send_ring_status_invalid_f());
 
         /*read get pointer and make equal to put*/
-        g->sim->send_ring_put = sim_readl(sim_linux, sim_send_get_r());
-        sim_writel(sim_linux, sim_send_put_r(), g->sim->send_ring_put);
+        g->sim->send_ring_put = sim_readl(g->sim, sim_send_get_r());
+        sim_writel(g->sim, sim_send_put_r(), g->sim->send_ring_put);
 
         /*write send ring address and make it valid*/
-        phys = sim_linux->send_bfr.phys;
-        sim_writel(sim_linux, sim_send_ring_hi_r(),
+        phys = nvgpu_mem_get_addr(g, &sim_linux->send_bfr);
+        sim_writel(g->sim, sim_send_ring_hi_r(),
                    sim_send_ring_hi_addr_f(u64_hi32(phys)));
-        sim_writel(sim_linux, sim_send_ring_r(),
+        sim_writel(g->sim, sim_send_ring_r(),
                    sim_send_ring_status_valid_f() |
                    sim_send_ring_target_phys_pci_coherent_f() |
                    sim_send_ring_size_4kb_f() |
                    sim_send_ring_addr_lo_f(phys >> PAGE_SHIFT));
 
         /*repeat for recv ring (but swap put,get as roles are opposite) */
-        sim_writel(sim_linux, sim_recv_ring_r(), sim_recv_ring_status_invalid_f());
+        sim_writel(g->sim, sim_recv_ring_r(), sim_recv_ring_status_invalid_f());
 
         /*read put pointer and make equal to get*/
-        g->sim->recv_ring_get = sim_readl(sim_linux, sim_recv_put_r());
-        sim_writel(sim_linux, sim_recv_get_r(), g->sim->recv_ring_get);
+        g->sim->recv_ring_get = sim_readl(g->sim, sim_recv_put_r());
+        sim_writel(g->sim, sim_recv_get_r(), g->sim->recv_ring_get);
 
         /*write send ring address and make it valid*/
-        phys = sim_linux->recv_bfr.phys;
-        sim_writel(sim_linux, sim_recv_ring_hi_r(),
+        phys = nvgpu_mem_get_addr(g, &sim_linux->recv_bfr);
+        sim_writel(g->sim, sim_recv_ring_hi_r(),
                    sim_recv_ring_hi_addr_f(u64_hi32(phys)));
-        sim_writel(sim_linux, sim_recv_ring_r(),
+        sim_writel(g->sim, sim_recv_ring_r(),
                    sim_recv_ring_status_valid_f() |
                    sim_recv_ring_target_phys_pci_coherent_f() |
                    sim_recv_ring_size_4kb_f() |
diff --git a/drivers/gpu/nvgpu/common/linux/sim.h b/drivers/gpu/nvgpu/common/linux/sim.h
index a9ec0dba..4b5e910c 100644
--- a/drivers/gpu/nvgpu/common/linux/sim.h
+++ b/drivers/gpu/nvgpu/common/linux/sim.h
@@ -2,7 +2,7 @@
  *
  * GK20A sim support
  *
- * Copyright (c) 2017, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -20,17 +20,16 @@
 #ifndef __SIM_LINUX_H__
 #define __SIM_LINUX_H__
 
+#include <nvgpu/nvgpu_mem.h>
 #include "gk20a/sim_gk20a.h"
 
 struct sim_gk20a_linux {
         struct sim_gk20a sim;
         struct resource *reg_mem;
         void __iomem *regs;
-        struct {
-                struct page *page;
-                void *kvaddr;
-                u64 phys;
-        } send_bfr, recv_bfr, msg_bfr;
+        struct nvgpu_mem send_bfr;
+        struct nvgpu_mem recv_bfr;
+        struct nvgpu_mem msg_bfr;
 };
 
 int gk20a_init_sim_support(struct gk20a *g);
diff --git a/drivers/gpu/nvgpu/common/linux/sim_pci.c b/drivers/gpu/nvgpu/common/linux/sim_pci.c
index 889eeb24..ea417615 100644
--- a/drivers/gpu/nvgpu/common/linux/sim_pci.c
+++ b/drivers/gpu/nvgpu/common/linux/sim_pci.c
@@ -20,47 +20,67 @@
 
 #include <nvgpu/log.h>
 #include <nvgpu/linux/vm.h>
-
+#include <nvgpu/bitops.h>
+#include <nvgpu/nvgpu_mem.h>
+#include <nvgpu/dma.h>
 #include "gk20a/gk20a.h"
 #include "os_linux.h"
 #include "sim.h"
 #include "hw_sim_pci.h"
 
-static inline void sim_writel(struct sim_gk20a_linux *sim_linux, u32 r, u32 v)
+static inline void sim_writel(struct sim_gk20a *sim, u32 r, u32 v)
 {
+        struct sim_gk20a_linux *sim_linux =
+                container_of(sim, struct sim_gk20a_linux, sim);
+
         writel(v, sim_linux->regs + r);
 }
 
-static inline u32 sim_readl(struct sim_gk20a_linux *sim_linux, u32 r)
+static inline u32 sim_readl(struct sim_gk20a *sim, u32 r)
 {
+        struct sim_gk20a_linux *sim_linux =
+                container_of(sim, struct sim_gk20a_linux, sim);
+
         return readl(sim_linux->regs + r);
 }
 
-static void kunmap_and_free_iopage(void **kvaddr, struct page **page)
+static int gk20a_alloc_sim_buffer(struct gk20a *g, struct nvgpu_mem *mem)
 {
-        if (*kvaddr) {
-                kunmap(*kvaddr);
-                *kvaddr = NULL;
-        }
-        if (*page) {
-                __free_page(*page);
-                *page = NULL;
+        int err;
+
+        err = nvgpu_dma_alloc(g, PAGE_SIZE, mem);
+
+        if (err)
+                return err;
+        /*
+         * create a valid cpu_va mapping
+         */
+        nvgpu_mem_begin(g, mem);
+
+        return 0;
+}
+
+static void gk20a_free_sim_buffer(struct gk20a *g, struct nvgpu_mem *mem)
+{
+        if (nvgpu_mem_is_valid(mem)) {
+                /*
+                 * invalidate the cpu_va mapping
+                 */
+                nvgpu_mem_end(g, mem);
+                nvgpu_dma_free(g, mem);
         }
+
+        memset(mem, 0, sizeof(*mem));
 }
 
 static void gk20a_free_sim_support(struct gk20a *g)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        /* free sim mappings, bfrs */
-        kunmap_and_free_iopage(&sim_linux->send_bfr.kvaddr,
-                               &sim_linux->send_bfr.page);
 
-        kunmap_and_free_iopage(&sim_linux->recv_bfr.kvaddr,
-                               &sim_linux->recv_bfr.page);
-
-        kunmap_and_free_iopage(&sim_linux->msg_bfr.kvaddr,
-                               &sim_linux->msg_bfr.page);
+        gk20a_free_sim_buffer(g, &sim_linux->send_bfr);
+        gk20a_free_sim_buffer(g, &sim_linux->recv_bfr);
+        gk20a_free_sim_buffer(g, &sim_linux->msg_bfr);
 }
 
 static void gk20a_remove_sim_support(struct sim_gk20a *s)
@@ -70,7 +90,7 @@ static void gk20a_remove_sim_support(struct sim_gk20a *s)
                 container_of(g->sim, struct sim_gk20a_linux, sim);
 
         if (sim_linux->regs)
-                sim_writel(sim_linux, sim_config_r(), sim_config_mode_disabled_v());
+                sim_writel(s, sim_config_r(), sim_config_mode_disabled_v());
         gk20a_free_sim_support(g);
 
         if (sim_linux->regs) {
@@ -82,35 +102,6 @@ static void gk20a_remove_sim_support(struct sim_gk20a *s)
         g->sim = NULL;
 }
 
-static int alloc_and_kmap_iopage(struct gk20a *g,
-                                 void **kvaddr,
-                                 u64 *phys,
-                                 struct page **page)
-{
-        int err = 0;
-        *page = alloc_page(GFP_KERNEL);
-
-        if (!*page) {
-                err = -ENOMEM;
-                nvgpu_err(g, "couldn't allocate io page");
-                goto fail;
-        }
-
-        *kvaddr = kmap(*page);
-        if (!*kvaddr) {
-                err = -ENOMEM;
-                nvgpu_err(g, "couldn't kmap io page");
-                goto fail;
-        }
-        *phys = page_to_phys(*page);
-        return 0;
-
- fail:
-        kunmap_and_free_iopage(kvaddr, page);
-        return err;
-
-}
-
 static inline u32 sim_msg_header_size(void)
 {
         return 32U;
@@ -120,7 +111,11 @@ static inline u32 *sim_msg_bfr(struct gk20a *g, u32 byte_offset)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        return (u32 *)(sim_linux->msg_bfr.kvaddr + byte_offset);
+        u8 *cpu_va;
+
+        cpu_va = (u8 *)sim_linux->msg_bfr.cpu_va;
+
+        return (u32 *)(cpu_va + byte_offset);
 }
 
 static inline u32 *sim_msg_hdr(struct gk20a *g, u32 byte_offset)
@@ -155,7 +150,11 @@ static u32 *sim_send_ring_bfr(struct gk20a *g, u32 byte_offset)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        return (u32 *)(sim_linux->send_bfr.kvaddr + byte_offset);
+        u8 *cpu_va;
+
+        cpu_va = (u8 *)sim_linux->send_bfr.cpu_va;
+
+        return (u32 *)(cpu_va + byte_offset);
 }
 
 static int rpc_send_message(struct gk20a *g)
@@ -171,10 +170,10 @@ static int rpc_send_message(struct gk20a *g)
                 sim_dma_target_phys_pci_coherent_f() |
                 sim_dma_status_valid_f() |
                 sim_dma_size_4kb_f() |
-                sim_dma_addr_lo_f(sim_linux->msg_bfr.phys >> PAGE_SHIFT);
+                sim_dma_addr_lo_f(nvgpu_mem_get_addr(g, &sim_linux->msg_bfr) >> PAGE_SHIFT);
 
         *sim_send_ring_bfr(g, dma_hi_offset*sizeof(u32)) =
-                u64_hi32(sim_linux->msg_bfr.phys);
+                u64_hi32(nvgpu_mem_get_addr(g, &sim_linux->msg_bfr));
 
         *sim_msg_hdr(g, sim_msg_sequence_r()) = g->sim->sequence_base++;
 
@@ -182,7 +181,7 @@ static int rpc_send_message(struct gk20a *g)
                 PAGE_SIZE;
 
         /* Update the put pointer. This will trap into the host. */
-        sim_writel(sim_linux, sim_send_put_r(), g->sim->send_ring_put);
+        sim_writel(g->sim, sim_send_put_r(), g->sim->send_ring_put);
 
         return 0;
 }
@@ -191,7 +190,11 @@ static inline u32 *sim_recv_ring_bfr(struct gk20a *g, u32 byte_offset)
 {
         struct sim_gk20a_linux *sim_linux =
                 container_of(g->sim, struct sim_gk20a_linux, sim);
-        return (u32 *)(sim_linux->recv_bfr.kvaddr + byte_offset);
+        u8 *cpu_va;
+
+        cpu_va = (u8 *)sim_linux->recv_bfr.cpu_va;
+
+        return (u32 *)(cpu_va + byte_offset);
 }
 
 static int rpc_recv_poll(struct gk20a *g)
@@ -202,7 +205,7 @@ static int rpc_recv_poll(struct gk20a *g)
 
         /* Poll the recv ring get pointer in an infinite loop */
         do {
-                g->sim->recv_ring_put = sim_readl(sim_linux, sim_recv_put_r());
+                g->sim->recv_ring_put = sim_readl(g->sim, sim_recv_put_r());
         } while (g->sim->recv_ring_put == g->sim->recv_ring_get);
 
         /* process all replies */
@@ -219,18 +222,19 @@ static int rpc_recv_poll(struct gk20a *g)
                 recv_phys_addr = (u64)recv_phys_addr_hi << 32 |
                                  (u64)recv_phys_addr_lo << PAGE_SHIFT;
 
-                if (recv_phys_addr != sim_linux->msg_bfr.phys) {
+                if (recv_phys_addr !=
+                                nvgpu_mem_get_addr(g, &sim_linux->msg_bfr)) {
                         nvgpu_err(g, "Error in RPC reply");
                         return -EINVAL;
                 }
 
                 /* Update GET pointer */
-                g->sim->recv_ring_get = (g->sim->recv_ring_get + 2*sizeof(u32)) %
-                        PAGE_SIZE;
+                g->sim->recv_ring_get = (g->sim->recv_ring_get + 2*sizeof(u32))
+                        % PAGE_SIZE;
 
-                sim_writel(sim_linux, sim_recv_get_r(), g->sim->recv_ring_get);
+                sim_writel(g->sim, sim_recv_get_r(), g->sim->recv_ring_get);
 
-                g->sim->recv_ring_put = sim_readl(sim_linux, sim_recv_put_r());
+                g->sim->recv_ring_put = sim_readl(g->sim, sim_recv_put_r());
         }
 
         return 0;
@@ -316,53 +320,41 @@ int nvgpu_pci_init_sim_support(struct gk20a *g)
         sim_linux->regs = l->regs + sim_r();
 
         /* allocate sim event/msg buffers */
-        err = alloc_and_kmap_iopage(g, &sim_linux->send_bfr.kvaddr,
-                                    &sim_linux->send_bfr.phys,
-                                    &sim_linux->send_bfr.page);
-
-        err = err || alloc_and_kmap_iopage(g, &sim_linux->recv_bfr.kvaddr,
-                                           &sim_linux->recv_bfr.phys,
-                                           &sim_linux->recv_bfr.page);
-
-        err = err || alloc_and_kmap_iopage(g, &sim_linux->msg_bfr.kvaddr,
-                                           &sim_linux->msg_bfr.phys,
-                                           &sim_linux->msg_bfr.page);
+        err = gk20a_alloc_sim_buffer(g, &sim_linux->send_bfr);
+        err = err || gk20a_alloc_sim_buffer(g, &sim_linux->recv_bfr);
+        err = err || gk20a_alloc_sim_buffer(g, &sim_linux->msg_bfr);
 
-        if (!(sim_linux->send_bfr.kvaddr && sim_linux->recv_bfr.kvaddr &&
-              sim_linux->msg_bfr.kvaddr)) {
-                nvgpu_err(g, "couldn't allocate all sim buffers");
+        if (err)
                 goto fail;
-        }
-
         /* mark send ring invalid */
-        sim_writel(sim_linux, sim_send_ring_r(), sim_send_ring_status_invalid_f());
+        sim_writel(g->sim, sim_send_ring_r(), sim_send_ring_status_invalid_f());
 
         /* read get pointer and make equal to put */
-        g->sim->send_ring_put = sim_readl(sim_linux, sim_send_get_r());
-        sim_writel(sim_linux, sim_send_put_r(), g->sim->send_ring_put);
+        g->sim->send_ring_put = sim_readl(g->sim, sim_send_get_r());
+        sim_writel(g->sim, sim_send_put_r(), g->sim->send_ring_put);
 
         /* write send ring address and make it valid */
-        phys = sim_linux->send_bfr.phys;
-        sim_writel(sim_linux, sim_send_ring_hi_r(),
+        phys = nvgpu_mem_get_addr(g, &sim_linux->send_bfr);
+        sim_writel(g->sim, sim_send_ring_hi_r(),
                    sim_send_ring_hi_addr_f(u64_hi32(phys)));
-        sim_writel(sim_linux, sim_send_ring_r(),
+        sim_writel(g->sim, sim_send_ring_r(),
                    sim_send_ring_status_valid_f() |
                    sim_send_ring_target_phys_pci_coherent_f() |
                    sim_send_ring_size_4kb_f() |
                    sim_send_ring_addr_lo_f(phys >> PAGE_SHIFT));
 
         /* repeat for recv ring (but swap put,get as roles are opposite) */
-        sim_writel(sim_linux, sim_recv_ring_r(), sim_recv_ring_status_invalid_f());
+        sim_writel(g->sim, sim_recv_ring_r(), sim_recv_ring_status_invalid_f());
 
         /* read put pointer and make equal to get */
-        g->sim->recv_ring_get = sim_readl(sim_linux, sim_recv_put_r());
-        sim_writel(sim_linux, sim_recv_get_r(), g->sim->recv_ring_get);
+        g->sim->recv_ring_get = sim_readl(g->sim, sim_recv_put_r());
+        sim_writel(g->sim, sim_recv_get_r(), g->sim->recv_ring_get);
 
         /* write send ring address and make it valid */
-        phys = sim_linux->recv_bfr.phys;
-        sim_writel(sim_linux, sim_recv_ring_hi_r(),
+        phys = nvgpu_mem_get_addr(g, &sim_linux->recv_bfr);
+        sim_writel(g->sim, sim_recv_ring_hi_r(),
                    sim_recv_ring_hi_addr_f(u64_hi32(phys)));
-        sim_writel(sim_linux, sim_recv_ring_r(),
+        sim_writel(g->sim, sim_recv_ring_r(),
                    sim_recv_ring_status_valid_f() |
                    sim_recv_ring_target_phys_pci_coherent_f() |
                    sim_recv_ring_size_4kb_f() |